Manual de Servicio Jac j2

Maintenance Manual for J2 Sedan Foreword

Maintenance Manual for J2 Sedan

Foreword Master Table of Contents

General Description &

Maintenance

Engine

Chassis

Body Electrical & Structure

Circuit Troubleshooting

This manual is intended to help the

professional maintenance technicians

authorized by JAC Passenger Car Sales

Company provide effective and correct

maintenance and service for JAC J2

Sedan series models. The warm service

and proper operation from the

professional maintenance technicians of

JAC passenger cars are essential for

ensuring customer satisfaction to JAC

passenger car products. Therefore, the

maintenance technicians must

understand this manual fully. This

manual should be placed in a handy

place for your convenient reference.

All contents of this manual including

pictures and technical parameters are

latest. In case maintenance works are

affected due to product improvement,

JAC Passenger Car Sales Company will

provide technical bulletins or

supplementary volumes. Therefore, you

should use this manual and pay close

attention to obtaining latest update

relevant information.JAC Passenger Car

Sales Company reserves the rights to

change, add or improve designs of its

products.

No part of this manual is allowed to be

reproduced or modified in any form,

including but not limited to electronic

media, paper, sound and image, and

mechanical media, without written

authorization from JAC Passenger Car

Sales Company.

Use of non genuine spare parts for

JAC passenger cars or nonconforming

oils during maintenance and service

processes of JAC passenger car

products may cause vehicle damage.

Chapter I General Description

Chapter II Maintenance

Chapter I Engine mechanical system

Chapter II Engine electrical system

Chapter III engine electronic control

system

Chapter I Clutch & Manual

Transmission

Chapter II Traveling system

Chapter III Braking system

Chapter I Body Electrical

Chapter II Body Structure

Maintenance Manual for J2 Sedan Contents

Contents of Overview and Service

Chapter I Overview..........................................................................................................1

Section I General Instructions ...................................................................................................... 1

I. Summary .............................................................................................................................. 1

II. Operations ............................................................................................................................ 1

Section II Vehicle Information ..................................................................................................... 2

I. Identification Information Position ........................................................................................ 2

II. Nameplate ............................................................................................................................ 2

III. Vehicle Identification Number (VIN) ..................................................................................... 3

IV. Engine Number..................................................................................................................... 4

Section III Lifting, Protection and Towing of Vehicle.................................................................. 6

I. Lifting of Vehicle ................................................................................................................... 6

II. Protection of Vehicle............................................................................................................. 6

III. Towing of Vehicle ................................................................................................................. 7

Chapter II Service............................................................................................................8

Section I Service............................................................................................................................... 8

I. Prepara tools ........................................................................................................................ 8

II. General Service.................................................................................................................... 8

III. Regular Service .................................................................................................................... 9

IV. Recommended Oil and Lubricant....................................................................................... 10

V. Service of Engine ............................................................................................................... 11

VI. Service of Chassis and Body ............................................................................................. 19

VII. Maintenance Data .............................................................................................................. 27

Maintenance Manual for J2 Sedan Overview

1

Chapter I Overview

Section I General Instructioooons

I. Summary

This Manual provides the procedures required by service operations, including:

1. Structure and composition

2. Principles

3. Dismantlement and installation steps

4. Inspection methods

5. Adjustment & commissioning methods

6. Common trouble diagnosis procedures

7. Technical parameters

The simple operations that can be conducted through the observation of vehicle are left out in this Manual. No description is given for the necessary basic skills of maintenance technicians in this Manual.

II. How to use

This Manual comprises four parts, i.e. engine volume, chassis volume, electrical appliance & structure volume of vehicle body and electric circuit inspection volume. In front of each part is given a detailed content index, in which you can find the section you want quickly.

This Manual provides following information:

1. Working principles;

2. Component position

3. Inspection and service specifications

4. Component dismantlement & installation steps

5. Common troubles and repair procedures

Such information are in compliance with current model at time published.


2

Section II Vehicle Information

I. Identification Information Position

Position of vehicle ID

1- Name plate of vehicle 2- ID number of vehicle

II. Nameplate

1. Position of nameplate: at the firewall of engine compartment.

2. Instructions of nameplate

Example of Nameplate

Made by China Anhui Jianghuai Automobile Co., Ltd.

Ex-factory no. Ex-factory date Jan. 2010

Max. gross weight Fixed number 5 persons

Engine Model Rated power

Engine displacement Model

Brand: Jianghuai

1

2


3

III. Vehicle Identification Number (VIN)

1) VIN position: on the nameplate or at the left bottom of windshield.

2) Illustration of VIN

Part 1: Word Manufacturer Identification (WMI), consists of 3 numbers according to GB16737, which should be applied, approved and filed. WMI for JAC is LJ1, which applicable for freight truck, incomplete vehicle, bus, passenger car, tractor and special vehicle of JAC. Word Manufacturer Identification (WMI) is shown in table below.

Table Worldwide Manufacturer Identification

ID Manufacturer Applicable Models

LJ1 JAC Co., Ltd, ANHUI Freight truck, incomplete vehicle, bus, passenger car, tractor,

special vehicle

Part 2: vehicle description Code (VDS), as specified in GB 16737, this part should be made up with 6 digitals to presents basic features of vehicle model.

VDS making-up:

Inspection digit

Code of engine type and rated power

Max. gross weight

Body type

Vehicle type

Truck wheelbase / passenger cars, buses and chassis length

Geographical region

Country

Manufacturer

Vehicle Description Code

Check Character

Digitals

Order number

Assembled in

Model year

Representative letter or number

Representative number

Digitals


4

① Vehicle type：2 Means passenger cars

F: 3 chambers & 4 doors

② Body type

G: 2 chambers & 5 doors

③ Max. Gross Weight: K: >1000-2000

④ Truck wheelbase / passenger cars, buses and chassis length: R> 2390 - 2600

1: gasoline ≤70Kw

⑤ Code of engine type and rated power 2: gasoline >70-90Kw

3: gasoline >90-110Kw

Part 3: indication of vehicle, 8 digitals

4:General Assembling Workshop of Passenger Car Manufacture Company

Factory assembled

7:General Assembling Workshop of Passenger Car Manufacture Company

8: 2008

Year 9: 2009

A: 2010

IV Engine Number

1. Position of engine number

Engine number is stamped on the exhaust side of cylinder block (See figure below).

Production SN

Factory assembled

Year

Digitals

Fig. 2.1.001


5

2. Meaning of Engine Number

3GB4.C – Engine model: 1.0 3-cylinder gasoline engine

A3408769:

A – the year of 2010

3 - engine type (petrol, local parts)

408769– Production SN

Fig. 2.1.002


6

Section III Lifting, Protection and Towing of Vehicle

I. Lifting of Vehicle

1. Vehicle’s Supporting Points

The positions of vehicle’s supporting points are shown in figure below.

Attention:

Don’t lift the vehicle by using the point other than those specified; otherwise vehicle body may be damaged.

Positions of Vehicle’s Supporting Points

2. Operation of Lifter

The lifter should be operated strictly in accordance with the specifications of manufacturer.

Caution:

The operation against the specifications may cause damage of vehicle or personnel injury or even death.

II. Protection of Vehicle

1. Appearance Protection

Be sure to use the four protection appliances including seat cover, steering wheel cover, gearshift lever cover, and foot mat before any operation. A protective pad must be applied on the fenders when engine hood is opened for inspection.

2. Preventive Measures before Welding

Since electrical components are installed on the vehicle, the following procedures must be carried out in order to avoid too large current through such components in welding:

1) Turn ignition switch to “OFF” position;

2) Disconnect negative pole of battery;

3) Ground the welding equipment carefully at a point nearby the welding area;

4) Cover other exposed equipment around the welding area to prevent solders from splashing on.

Supporting point


7

III. Towing of Vehicle

If vehicle needs to be towed, please contact the local authorized after-sales service center or a special vehicle towing service company.

1. Towing with tractor

Caution:

No passenger allowed in the vehicle being towed;

Don’t allow the traction speed over the safety speed or the stated speed limit;

Make sure the vehicle being towed are fixed firmly;

Operation against above-mentioned precautions may cause personnel injury.

2. Towing with wheel lifter

1) Turn ignition switch to “ACC (accessory)” position;

2) Turn on the hazard warning indicator flashing;

3) Shift to neutral position;

4) Release parking brake;

5) Make sure the front wheels are away from ground.

Attention:

If it is necessary to tow the vehicle from the back, the supporting wheel of traction device should be set under front wheels. Don’t make front wheels in contact with ground in towing; otherwise the transmission may be seriously damaged.

3. Emergency towing

If no towing vehicle is available under emergency, a rope may be fixed to the emergency towing hole under the vehicle for temporary traction.

1) Front towing hole: It is under the front bumper. A driver is required in the vehicle for steering and braking purposes in towing. Such traction method is applicable only on hard pavement with towing distance and speed limited to certain extent. In addition, such parts as wheels, axles, drive system, steering system, and brakes must be in good conditions.

Caution:

The vehicle may be damaged when towed by rope.

In order to minimize such damage,

① If no other towing equipment is available, the towing hole must be used;

② Always tow the vehicle from its forehead;

③ Keep the towing rope away from the bumper;

④ Check the towing rope by pulling it to make sure both ends are fixed firmly on the towing hole.

2) Rear towing hook: It can used to tow another vehicle only under emergency (when a vehicle is trapped in a ditch, heavy snow or mud pit). When using the rear towing hook, always keep the rope or chain perpendicular to hook. Don’t apply force to the towing hook from any ohter directions. Don’t start towing sharply otherwise damage may be caused.

Maintenance Manual for J2 Sedan Service

8

Chapter II Service

Section I Service

I. Preparation

1. Maintenance Tools

List of Maintenance Tools

No. Tools Outside View Description

1 Power tool

For dismantlement and

installation of bolts and

nuts

2 Ignition plug

socket

For dismantlement and

installation of ignition

plug

II. General Service

General Service means the inspection and maintenance items which should be performed everyday during normal use of vehicles. These service items are very important, for normal operation performance of vehicle. The owners can perform these inspections by themselves, or go to a JAC franchised store for assistance. Followed is content of general service:

1. Exterior of Vehicle

The following inspection and maintenance items should be frequently conducted.

List of Items to be Frequently Inspected for the Exterior of Vehicle

Item Inspection

Tyre Use an air gauge to inspect the pressure of tyres (including spare tyre) in the service station regularly; adjust pressure in accordance with technical data if necessary. Check whether there’s any damage, crack or excessive worn tear carefully.

Windshield Clean the windshield regularly. Check whether there’s any crack or other damage of the windshield every six months or more frequently. Repair as required.

Windshield wiper blade

If the wiper doesn’t work efficiently, check for worn or torn.

Door and engine hood

Check whether all of the doors, engine hood, boot cover and tail door can be normally opened and closed normally, whether all the door locks are locked closely. Lubricate as required. Moreover, If the vehicle often travels on the salt-spread roads or in the areas with corrosive substances, always inspect lubricating conditions.

Tyre exchange The tyre exchange should be conducted after each 8000 km traveling.


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Vehicle lamps Verify that headlamps, brake indicators, tail lamps, turning signal indicator and other lighting units work normally and have been stably fixed. Meanwhile, inspect focusing function of headlamp.

2. Interior of Vehicle

The following inspection and maintenance items should be performed regularly.

List of Items to be Regularly Inspected for Interior of Vehicle

Item Inspection

Alarm light and buzzer

Make sure all the alarm lights and buzzers are working normally.

Windshield wiper and washer

Check whether the wiper and cleaner are working normally; check whether there is any crack in the wiper.

Windshield defroster Check whether the air can be correctly bled from the air outlet of defroster, whether the heater or air conditioner can breathe enough air during operation of heater or air conditioner.

Steering wheel Check whether the free travel of steering wheel is in the standard range. Inspect changes of steering performance, such as the free travel beyond range, hard steering and abnormal noise etc.

Seat Belt Check whether all the components of seat belt system are flexible and working normally and fixed firmly and stably. Check seat belt for cracking, worn out or other damage.

Throttle pedal Check whether the pedal can be operated smoothly, make sure that the pedal would not be seized or loaded unevenly. Keep floor pad away from the pedal.

Brake pedal and booster

Check if the pedal can be operated smoothly; make sure the pedal still keeps an appropriate distance from the bottom plate when it is completely pressed down. Inspect the function of brake vacuum booster. Make sure that the bottom plate pad is away from the pedal.

Parking brake Check travel of handle.

3. Engine and Vehicle Chassis

The following inspection and maintenance items should be regularly performed.

List of Items to be Regularly Inspected for the Engine and Vehicle Chassis

Item Inspection

Cleaning liquid for windshield Check whether there is adequate cleaning liquid in reservior.

Level of engine coolant Check the coolant level when the engine is cold.

Engine oil level Stop the vehicle on a level ground and turn off engine; check oil level.

Levels of brake fluid and clutch fluid Make sure that the levels of brake fluid and clutch fluid are between the “MAX” line and “MIN” marks on reservoir.

Battery Inspect conditions of voltage and battery poles.

Liquid leakage After the vehicle has been stopped for a while, check for any leakage of fuel, engine oil, coolant or other liquid under the vehicle. Water drop from the air conditioner which has just been used is normal. In case of obvious leakage or petrol fume, find out the causes and repair immediately.

III. Regular Service

Each item is expressed in travel distance and time (months), whichever comes first (distance or time)

should be used as the basis for inspection.


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Service operational code: I-examination; R-replacement; C-washing

Service cycle (odometer readings and the number of months, whichever comes first)

1000km 1 10 20 30 40 50 60 70 80 90 100 Item

Month — 6 12 18 24 30 36 42 48 54 60

1 Driving belt I: every 10,000 km or 6 months

R: every 60,000 km or two years

2 Check oil and gas control systems of crankcase for normal working

I I

3 Spark plug I I R I I R I I R I

4 Change coolant R R R R R

General conditions of use C: every 5,000km R: 15,000km 5

Air filter element Harsh conditions of use C: every 3,000km R: 10,000km

General conditions of use R: every 5,000 km or 6 months 6

Oil and oil filter Harsh conditions of use R: every 3,000 km or 3 months

7 Carbon monoxide content with engine idling I I I I I I I I I I

8 Ignition timing I I I I I

9 Hose I I I I I I I I I I

10 Exhaust fittings leakage I I I I I I I I I I

11 Throttle body C C C C C

12 Injector C* C* C* C* C* C* C* C* C* C*

13 Valve clearance I I I I I I

Notes:

C *---For cleaning operation of fuel injector, it is recommended that dedicated fuel injector cleaning

analyzer is used; Check every 3 months or 5000km; if there are nozzle clogging or blockage failures and

they are non-product quality problems, they should be maintained at users’ expenses.

"Harsh conditions of use" specifications are only used in severe conditions of use of vehicles. Harsh

conditions of use include the following:

① Driving in dusty areas or the vehicle is regularly exposed to salty air or sea water.

② Driving on rugged road, road with water accumulation or on mountain roads.

③ Driving in cold areas.

④ In the cold season, the engine idles a long time or used frequently in short-distance traveling.

⑤ Frequent use of brakes, regular emergency braking. .

⑥ As tractor

⑦ As taxi or leasing

⑧ At temperatures above 32 , driving in urban heavy traffic for more than 50% of the total travel

time.


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⑨ At a temperature below 30 , driving at 120km/h or higher speed limits for more than 50% of the

total travel time.

⑩ Overloaded traveling.

IV. Recommended Oil and Lubricant

Which listed below are the types of oil and lubricant recommended by JAC:

List of Recommended Oil and Lubricant

Item Capacity (L) Recommended oil / lubricant

Engine oil 3.8

Factory filled oil: SAE10W-30

Ambient temperature for use: -25 - 35

User must select the appropriate oil according to local ambient temperature

Quality level: SJ or above

Cooling system 5.5 High-quality HF-C anti-freezing solution

Manual transmission gear oil 2.0 API GL-4, SAE 75W/90

Brake fluid and clutch fluid 0.56±0.05 DOT4 (Great Wall)

AC refrigerant 600±25g R134a

Wiper cleaning liquid 3 Water

AC compressor lubricating oil 0.12 PAG56

V. Service of Engine

1. Inspection of Driving Belt

Warnings

Be sure to operate only with engine stopped.

1) Check for belt aging, crack, wear and oil stain. Replace as required.

2) Check the belt tension at the mid-point between both pulleys.

Inspection should be conducted in the engine cold state or when it has been stopped after 30min.

Range of tension force – Alternator belt: 500±50N Please be noted that the experience equation for

tensioning force of reused belt is as below: Tensioning force for new belt * 1.2/1.5

If the belt tension is out of range, adjust.

Attention：：：：

For checking belt tension installation, firstly adjust to the specified value, then turn the crank

for more than two laps to re-adjust to the specified value in order to avoid tension between

pulleys changing.

2. Adjustment of Tension


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Tension Adjustment Table

Part Adjusting Method

Generator belt Turn adjusting bolt of generator belt

Attention:

After replaced with new belt, adjust the belt tension so as to meet requirements.

During installation of belt, make sure that the belt is in correct engagement with the pulley

groove.

Don’t spill any engine oil or engine coolant on the belt.

Do not over wind or bend belt; for used belt, be aware of mounting direction.

3. Change Coolant of Engine

Caution:

In order to avoid scald, never change coolant with engine hot.

Wrap the radiator cap with thick cloth and unscrew it carefully. Release the pressure inside

the radiator at first, and then completely unscrew it to open the radiator.

Be aware not to spill the engine coolant on the driving belt.

1) Drain engine coolant

① Dismount the right deflector of engine. See “Engine Deflector”.

② Open the water drain plug at the bottom of radiator, and then open the cap of radiator.

③ If necessary, please dismount coolant reservoir, drain the engine coolant, and reinstall it after cleaned.

④ Check if there’s any foreign matter such as rust or any color change in the discharged engine coolant.

In case it is polluted, please wash the engine cooling system. See “Washing the Cooling System” please.

2) Refill engine coolant

① Reinstall dismantled coolant reservoir and the drain plug of radiator.

Attention:

The drain screw plug must be cleaned, a new O-ring must be installed.

② Make sure that all the hose clamps have been stably tightened.

③ Dismount the upper cover of air filter and the intake hose. Please refer to “Air Filter Assembly”.

④ Disconnect outlet tube of heater pipe. Please lift the hose as high as possible.

⑤ Fill coolant into radiator and coolant reservoir to specified level; the engine coolant must be filled slowly, such as to gradually bleed air from the system.

Attention:

Please mix the original JAC engine coolant or equivalent product with water. See “Recommended Oil and Lubricant”.


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If coolant overflows from the heater outlet pipe, disconnect pipe and reconnect and then continue the filling of coolant.

⑥ Install air filter upper cover and intake hose. Please refer to “Air Filter Assembly”.

⑦ Install radiator cap.

⑧ Warm up the engine until the thermostat is switched on.

Examine if there’s warm water flowing out by touching the lower hose of radiator, such as to check whether the thermostat has been switched on.

Attention:

Watch on engine temperature meter, such as to avoid overheating of engine.

⑨ Stop the engine, allow engine temperature drops.

The cooling time can be reduced by using fan.

⑩ Fill engine coolant in coolant until the MAX level reached.

⑪ Install radiator cap, and repeat steps ③-⑨ for more than two times until the level of engine coolant

doesn’t go down any more.

⑫ Start engine, check for any leakage in the cooling system.

3) Wash cooling system

① Install water drain plug of radiator and coolant reservoir removed above.

Attention:

The drain screw plug must be cleaned, a new O-ring must be installed.

② Dismount air filter upper cover and the intake hose. Refer to “Air Filter Assembly”.

③ Disconnect outlet tube of heater pipe. Please lift the hose as high as possible.

④ Fill engine coolant into the radiator and coolant reservoir, install cap of radiator.

If coolant overflows from the heater outlet pipe, disconnect pipe and reconnect and then continue

filling of coolant.

⑤ Install air filter upper cover and intake hose. Refer to “Air Filter Assembly”.

⑥ Start the engine, warm up it to normal working temperature.

⑦ Speed up the engine for several times without load.

⑧ Stop engine, and wait till engine cooled down.

⑨ Discharge coolant inside system. Refer to “Draining Engine Coolant”.

⑩ Repeat steps ①-⑨ until the radiator starts to discharge clear water.

4. Inspection of Cooling System

Caution:

Never open the radiator cap with engine hot. The high temperature and high pressure liquid

overflowing from the radiator may cause severe scald.

Wrap the radiator cap with thick cloth and unscrew it for 1/4 circle to release the pressure

inside radiator at first, and then completely unscrew it to open radiator.


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1) Inspection of cooling system hose

Check the hose for incorrect installation, crack, damage, loose connection, worn or ageing.

Please repair or replace the damaged components as required.

2) Inspection of radiator cap

① Check valve seat of radiator cap

Check whether the valve seat expands outward, i.e. when the plunger is vertically lifted from the top,

end of plunger is out of view.

Check valve seat for any dust or damage.

② Pull out negative pressure valve to open it,

and upon the pressure is released, check

whether it can be completely closed.

Make sure there isn’t any smudge or damage

on the valve seat.

Make sure that the valve seat can be normally

opened and closed.

③ Check the pressure released by radiator cap.

Standard: 78-98 KPa

Limit: 59 KPa

— Connect the radiator cap to radiator leak

detector, paste engine coolant onto the

sealing face of cap.

If any failure is found in above-mentioned

three inspection items, replace radiator cap.

Attention:

For installation of radiator cap, please wipe the radiator filler carefully to clear away any

paraffin residue or foreign substance.

3) Inspection of radiator

Check for any mud or clogging situation in radiator. If any, clean with following method.

Be aware not to twist or damage the radiation fins.

In case of cleaning without dismounting the radiator, all accessories such as cooling fan, wind

collection hood and horn should be dismounted. Wrap connectors of wire harness with adhesive

tape for water proofing.

① Wash back of radiator fins from the top to the bottom with water spraying normal to radiator.

② Wash each surface of the radiator every other minute.

③ In case no dirt is washed away from the radiator, the washing work should be stopped.

Fig. 2.2.001

Fig. 2.2.002


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④ Blow the back of radiation core with compressed air vertically from top to bottom. The pressure of

compressed air should be less than 490 KPa, and a distance of more than 30 cm should be kept.

⑤ Blow radiator core surface with compressed air every other minute until no water can be blown

away.

4) Check for leakage of cooling system

① Check for leakage through applying pressure to the cooling system with a leakage detector of

radiator cap.

Test pressure: 157 KPa

Caution:

Never remove the radiator cap with engine hot;

otherwise the high temperature and high

pressure liquid overflowing from the radiator

may cause severe scald.

Attention:

A pressure exceeds the specified test

pressure may cause damage to the radiator.

In case the engine coolant is found decreased, please refill engine coolant into the radiator.

② If any component is found damaged, repair or replace.

5. Inspection of Fuel Pipeline

Check the fuel pipeline, fuel filler cap and fuel tank for

incorrect installation, leakage, crack, damage, loose

connection, worn or aged.

Repair or replace damaged component as

required.

6. Replacement of Air Filter

1) Dismantlement

① Unscrew lock bolt of air filter upper cover lift up the

cover.

Fig. 2.2.005

Fig. 2.2.004

Fig. 2.2.003

Engine Fuel pipeline

Fuel tank


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② Take off air filter element.

2) Inspection After Dismantlement

The air filter must be regularly cleaned or replaced

according to recommended schedule. Please

refer to “Regular Service”.

Blow back of air filter element with compressed air until nothing can be blown away.

3) Installation

Install with steps contrary to dismantlement.

7. Replacement of Engine Oil

Attention:

Be careful not to be scalded since oil temperature is high.

Long-time direct contact between skin and the used oil should be avoided. In case contacted,

wash with soap or detergent thoroughly as soon as possible.

1) Warm up the engine, and check for any oil leakage in the engine compartment. Refer to “Leakage of

engine oil”.

2) Stop engine and wait for ten minutes.

3) Loosen engine oil filler cap, and then remove the oil drain screw plug.

4) Discharge engine oil.

5) Install the oil drain screw plug with new gasket.

Attention:

Any dirt such as iron debris on oil drain screw plug must be cleaned, and new gaskets

should be installed.

Tightening torque of oil drain bolt: 34-44 N·m.

6) Refill new oil.

For specification and viscosity of engine oil, please refer to “Recommended Oil and Lubricant”.

Engine oil quantity: 3.8L

Attention:

During the filling of engine oil, please do not remove oil gage.

The filling amount of engine oil may vary according to oil temperature and oil drain time.

Quantity above is for reference only.

Fig. 2.2.006


17

Oil rule should be used all the way to check whether the filling amount of engine oil is

proper.

7) Warm up the engine, check areas around the oil drain screw plug and oil filter for leakage.

8) Stop engine and wait for ten minutes.

9) Inspect oil level. See also “Engine oil level”.

8. Change Oil Filter

1) Dismantlement

① Use oil filter wrench to dismount the filter.

Attention:

JAC original engine oil or equivalent product should be used.

Be careful not to be scalded since engine and oil are hot.

During dismantlement, a cloth should be prepared to wipe up the leaked or splashed oil.

Please keep the driving belt free from engine oil.

Clean any oil splashed on engine and vehicle.

2) Installation

① Clear any foreign substance on mounting

surface of oil filter.

② Paste a film of engine oil onto the oil seal

surface of new filter.

③ Tighten.

Tightening torque: 10-12N·m

Attention:

The engine oil filter must be tightened with a filter wrench.

Manual tightening may cause oil leakage due to the inadequate tightening torque.

3) Post-installation inspection

① Inspect oil level, and fill engine oil when it is inadequate. See also “Engine Oil”.

② Start engine, check for any oil leakage.

③ Stop engine and wait for ten minutes.

④ Inspect oil level, and fill engine oil. See also “Engine Oil”.

9. Replacement of Ignition Plug

Fig. 2.2.007


18

1) Dismantlement

① Dismount the engine hood. See also “Intake manifold”.

② Disassemble the ignition coil. Please refer to “Ignition Coil”.

③ Dismount the ignition plug with plug socket.

Attention:

Be aware not to drop or shock the ignition plug.

2) Inspection after the dismantlement

Generally, the standard ignition plug should be used.

In the following conditions, if carbon deposition frequently occurs with standard ignition plug, the hot

ignition plug should be used:

Engine is frequently started.

Ambient temperature is low.

In the following conditions, in case ignition knock frequently occurs with standard ignition plug, the cold

ignition plug should be used:

Long-time traveling on the expressway;

Engine is frequently running with high speed.

Attention:

Be sure not to drop or shock the ignition plug.

Steel brush should not be used for cleaning.

If there’s carbon deposition on ignition plug end, remove with ignition plug cleaner.

During the replacement interval, the ignition plug gap should be checked when it is

necessary.

Ignition plug gap: 0.7-0.8 mm

3) Installation

Install with steps contrary to dismantlement. Tightening torque of ignition plug: 25-30 N·m.

10. Replacement of Fuel Filter

1) Dismantlement

Caution:

Be sure to read the “General Precautions” before any handling of fuel system. See “General

Precautions”.

① Open the fuel filler cap.


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② Release pressure inside fuel tank.

③ Remove the rear seat cushion. See “Rear Seat”.

④ Dismount the fuel tank service cap.

⑤ Dismount the fuel filter and fuel pipe.

For detailed information, please refer to “Fuel Filter”.

2) Installation

Be aware of following precautions to install with steps contrary to dismantlement.

① Installation direction of fuel filter

Be aware of installation direction of fuel filter.

Towards inlet tube.

② Installation of pipe fitting.

3) Post-installation inspection

Check for any fuel leakage with following steps.

① Turn ignition switch to “ON” (with engine stopped), and then check for leakage at the joints of fuel

pipeline.

② Start engine and run with increased speed, check again for fuel leakage at the joints of fuel pipeline.

11. Inspect the Evaporator passage of Fuel Evaporative Emission System (EVAP)

1) Visually check whether the installation position of EVAP evaporator pipeline is correct, and if it is

free from leakage, crack, damage, loose connection, scratching or ageing etc.

2) Check vacuum release valve of fuel tank cap for blockage or sticking etc. See “Fuel Evaporative

Emission System”.

VI. Service of Chassis and Body

1. Inspection of Exhaust System

Check for proper positions of exhaust pipe, muffler and fixed support, and anyleakage, crack, damage,

loose connection, worn or ageing.

Fig. 2.2.008


20

In case any component is found damaged,

repair or replace.

2. Inspection of Clutch Fluid Level and Leakage

If the fluid level is low, check clutch system for any leakage.

3. Inspection of Clutch System

Check for correct installation positions of liquid pipelines and operation cylinders, and any crack,

damage, loose connection, worn or ageing.

4. Inspection of Manual Transmission Gear Oil

Inspect oil level and whether there is any leakage. For detailed information, refer to “Inspection of

Manual Transmission Oil”.

5. Change Manual Transmission Gear Oil

1) Thoroughly drain oil from drain plug, and then refill with new gear oil. For detailed information, refer

to “Change Manual Transmission Oil”.

2) Inspect oil level. For detailed information, refer to “Inspection of Manual Transmission Oil Level”.

6. Wheel Balance

1) Dismantlement

① Dismount the wheel(s) need to be adjusted.

② Dismount the old balance blocks from both sides of the wheel, clear any foreign matters from treads

of tyre.

Note: for new tyre(s), the tape on the tyre should be removed.

Attention:

During dismantlement, be careful not to scratch the tyre.

2) Adjusting wheel balance

① Take the center hole as guide to install the wheel on balancer. Start the balancer.

② When unbalance values of both inner side and outer side of tyre have been indicated on the display

of wheel balancer, multiply the unbalance value of outer side with 5/3, so as to define the weight of

balance blocks which will be actually applied. Then, select the outer side balance block of which

Fig. 2.2.009


21

weight is nearest to the calculated value, and install it to the specified outer side position, or at the

specified angle relative to wheel.

Attention:

The balance block of outer side should be installed before inner side.

Prior to the installation of balance block, fitting surface on wheel must be thoroughly

cleaned.

a. Install the balance block to the position indicated in figure below.

b. As shown in the figure, during installation of

balance block on the wheel, the balance block

should be placed in the groove area on the

wheel inner wall, and fix with its center

towards the position (or angle) indicated by

the wheel balancer.

Attention:

The balance block should not be reused; it should be replaced every time.

At most three balance blocks are allowed to be installed.

The original balance blocks should be used any time.

c. In case the calculated weight of balance block

is more than 50 g, the two balance blocks

should be installed in a line.

Attention:

Never install a balance block on another

one.

③ Restart the wheel balancer.

④ At position (or angle) indicated by the wheel

balancer, knock in the balance block at the

inner side of wheel.

Attention:

At most two balance blocks are allowed to be installed.

⑤ Start the balancer. Make sure the residual unbalance value of both inner side and outer side is only

5 g or less.

In case the residual unbalance value of either side is more than 5 g, please repeat the installation

steps for balance block.

Fig. 2.2.010

Fig. 2.2.011

Stuck weight

Towards the groove

Position (or angle) indicated by the wheel balancer

Center of gravity

Position (or angle) indicated

by the wheel balancer


22

Allowable maximum unbalance:

7. Tyre Exchange

Tyre exchange should be performed every

8000 km.

Tyre exchange should also be performed when the

new tyre is put on.

Note: As shown in the figure is the recommend

method for tyre exchange.

8. Inspection for Brake Fluid Level and Leakage

If fluid level is low, please check brake system for

leakage.

9. Inspection of Brake System Pipeline and

Cable

Check for correct positions of brake pipeline and

parking brake cable, and any leakage, worn,

scratching or ageing etc.

10. Change Brake Fluid

Attention:

Refill brake fluid.

Discharged brake fluid must not be reused.

In order to keep the paintwork free from damage, be sure not to splash brake fluid onto the

paintwork. If the fluid is splashed onto the paintwork, please clean with water immediately.

Fig. 2.2.012

Fig. 2.2.014

Fig. 2.2.013

Highest line

Lowest line No

rma

l


23

1) Insert the ethylene tube onto release valve.

2) Press on the brake pedal to loosen the

release valve, and then discharge brake fluid

slowly.

3) Wash the inner side of fluid reservoir and refill with new brake fluid.

4) Loosen the release valve, press down the

brake pedal slowly, and then release. Repeat this

operation every other 2 or 3 s until there’s outflow

of new brake fluid, and then step on the brake

pedal to close the release valve. Repeat there

procedures for all wheels.

5) Bleed air. See also “Air Bleeding of Brake Pipeline”.

11. Inspection of Brake

1) Brake disc

Check for worn or damage.

List of Standard Specification of Brake Disc

Type Floating caliper type / ventilated disc

Brake disc diameter 241 mm

Brake disc thickness 19 mm

Friction block thickness 9 mm

Brake disc

Cylinder bore 51 mm

2) Brake drum

Check whether the inner diameter and circular runout of brake drum are in the scope of standard values.

If not, corresponding processing or replacement should be performed.

Fig. 2.2.015

Fig. 2.2.016


24

Standard Specification Table of Brake Drum

Type Leading trailing shoe brake

Brake drum diameter 204 mm

Cylinder bore of brake slave cylinder 17.46 mm

Clearance adjustment Automatically

Brake drum

Circular runout < 0.05 mm

3) Brake caliper

Check for any oil leakage.

4) Rear brake slave cylinder

Check for any leakage.

5) Front brake shoe

Check for worn or damaged conditions.

Standard thickness: 9 mm

Limit thickness: 2 mm

Fig. 2.2.017

Fig. 2.2.018

Fig. 2.1.019


25

6) Rear brake shoe

Check the brake shoe thickness and its contact

state with the brake drum. If it fails to meet the

requirement, replace.

Standard thickness of brake shoe (A): 5 mm

Allowable limiting thickness (A): 1 mm

12. Inspection of Steering Gear and Pull-rod

1) Steering gear

Check whether the steering gear housing and

dust boot are free from looseness, damage

and grease leakage.

Check whether its connection with the

steering column is loose.

2) Steering pull-rod

Check ball joint, dust boot and other components for loosening, worn, damage and grease leakage.

13. Check the pipeline.

Stop engine, check fluid level in reservior.

Attention:

Be sure not to fill steering fluid excessively.

Check for proper installation position of pipeline, and

any leakage, crack, damage, loose connection, worn

or ageing.

14. Axle and Suspension Components

Check for proper clearance between front/rear axles and suspension components and any crack,

damage, worn or other damages.

Fig. 2.2.020

Fig. 2.2.021

Fig. 2.2.022

Check the leakage of lubricating grease

Check the tightening torque


26

Rock each wheel to check for proper clearance.

Inspect operation conditions of wheel bearings.

Check axle, suspension nut and bolt for loosening.

Check shock absorber for oil leak or other damages.

Check the suspension ball joint for grease leakage;

check ball joint dust boot for crack or other damages.

15. Inspection of Drive Shaft

Check dust boot and drive shaft for any crack, worn,

damage or grease leakage.

16. Lubricating Door Lock, Hinge and Engine Hood Lock Pin

Lubricating Points of Door Lock, Hinge and Engine Hood Lock Pin

Fig. 2.2.023

Fig. 2.2.024

Fig. 2.2.025


27

17. Inspection of Seat belt, Tuckle and Pre-tensioner

Attention:

The seat belt assembly including retractor and other accessories (such as fixing bolt, guide

rail device) should be inspected every time after collision.

We suggest that you should replace seat belt assembly after collision, unless it is free of any damage

after slight impact.

And the seat belt assembly which is not used during the accident should also be checked, please

replace any damaged seat belt assembly.

In case a front collision which activates both driver and passenger’s airbags happens, the seat belt

pre-tensioner should be replaced, even though the seat belt is not used at all.

If any component of seat belt assembly has problems, please do not repair it, but replace the seat

belt assembly.

In case the seat belt is broken, worn or damaged, don’t repair but replace the seat belt assembly.

Be sure not to lubricate the lock tongue and snap ring.

Use original seat belt assembly of JAC.

Check whether the anchorage is loose.

Check whether the seat belt is damaged.

Check whether the motion of retractor is flexible.

While the snap ring open, check whether the snap ring and lock tongue function normally.

VII. Maintenance Data

1. Tightening Torque of Standard Parts

Tightening Torque List of Standard Parts

Torque (N·m) Nominal Diameter of

Thread Pitch

Head mark 4 Head mark 7

M5 0.8 3-4 5-6

M6 1.0 5-6 9-11

M8 1.25 12-15 20-25

M10 1.25 25-30 30-50

M12 1.25 35-45 60-80

M14 1.5 75-85 120-140

M16 1.5 110-130 180-210

M18 1.5 160-180 260-300

M20 1.5 220-250 360-420

M22 1.5 290-330 480-550

M24 1.5 370-420 610-700


28

Attention:

Tightening torques listed above are the standard values which are applicable for following

conditions:

a. Steel, plating nuts and bolts.

b. Plated steel plain washers.

c. All the dry nuts, bolts and gaskets.

The torques listed above are not applicable for following conditions:

a. When the component is to be tightened with spring or tooth washer;

b. Tightening of the plastic parts.

c. Self-tapping screw or self-locking nut.

d. Oiled thread and surface.

In following conditions, the torques listed above should be correspondingly reduced:

a. if a spring washer is used, the torque should be reduced to 85%.

b. If bolt surface is coated with oil, the torque should be reduced to 85%.


Engine Volume

Chapter I Mechanical Part of Engine........................................................ 33

Section I Engine Body...............................................................................................33

I. General Precautions ................................................................................................. 33

II. Precautions on Sealant ............................................................................................ 34

III. Preparation ................................................................................................................ 36

IV. Engine Assembly ...................................................................................................... 39

V. Drive Belt.................................................................................................................... 43

VI. Air Filter and Air Duct ............................................................................................... 45

VII. Intake Manifold and Exhaust Manifold ................................................................... 47

VIII. Exhaust System......................................................................................................... 51

IX. Timing sprocket mechanism ................................................................................... 53

X. Camshaft and balance shaft assembly................................................................... 58

XI. Cylinder head............................................................................................................. 64

XII. Valves ......................................................................................................................... 68

XIII. Cylinder Body Assembly.......................................................................................... 72

XIV. Diagnosis of Common Troubles.............................................................................. 86

XV. Parameters for Maintenance.................................................................................... 88

Section II Engine Lubrication System .....................................................................92

I. Precautions................................................................................................................ 92

II. Preparation ................................................................................................................ 93

III. Engine Oil................................................................................................................... 94

IV. Oil Filter ...................................................................................................................... 96

V. Oil Pan and Engine Oil Pump .................................................................................. 98

Section III Cooling System of Engine..................................................................102

I. Cooling Circuit......................................................................................................... 102

II. Engine Coolant........................................................................................................ 103

III. Radiator.................................................................................................................... 105

IV. Radiator Cooling Fan.............................................................................................. 107

V. Water Pump ............................................................................................................. 107

VI. Thermostat Sub-assembly ..................................................................................... 109

VII. Water Piping Sub-assembly................................................................................... 111

VIII. Trouble Analysis ..................................................................................................... 112

IX. Parameters for Maintenance.................................................................................. 113


Section IV Fuel Supply System of Engine...........................................................114

I. General Precautions ............................................................................................... 114

II. Preparation .............................................................................................................. 115

III. Fuel System ............................................................................................................. 115

IV. Fuel Injector and Guide Rail .................................................................................. 116

V. Fuel Filter ................................................................................................................. 119

VI. Fuel Pump Assembly .............................................................................................. 122

VII. Fuel Tank Assembly ............................................................................................... 126

Section V Emission Control System of Engine ..................................................128

I. Fuel Evaporation Control System ......................................................................... 128

II. Forced Ventilating System of Crankcase ............................................................. 132

Chapter II Electrical Part of Engine...................................................... 135

Section I Ignition System......................................................................................135

I. Ignition coil .............................................................................................................. 135

II. Diagnosis of Common Troubles............................................................................ 137

III. Parameters for Maintenance.................................................................................. 137

Section II Starting and Charging System ............................................................138

I. Principle Diagram of Starting and Charging System .......................................... 138

II. Battery ...................................................................................................................... 138

III. Starting System ....................................................................................................... 141

IV. Charging System..................................................................................................... 149

Chapter III Electronic Control System of Engine ................................ 155

Section I Precautions............................................................................................155

I. Precautions of Supplemental Restraint System (SRS)....................................... 155

II. General Precautions ............................................................................................... 155

III. Precautions in Maintenance .................................................................................. 155

IV. Common tools for diagnose .................................................................................. 157

V Precautions for On-board diagnose (OBD) system of engine ........................... 160

Section II Structural Principle and Inspection of Engine Control System .......163

I. System Description................................................................................................. 163

II. Multiple-point Fuel Injection System .................................................................... 164

III. On-board Diagnosis System .................................................................................. 167

IV. Engine Trouble Diagnosis...................................................................................... 173


Section III Structural Principle and Inspection of Engine Electronic Components

..................................................................................................................................179

I. Intake Manifold Absolute Pressure (MAP/MAT) Sensor ..................................... 179

II. Engine Coolant Temperature (ECT) Sensor......................................................... 181

III. Throttle Position Sensor ........................................................................................ 183

IV. Crankshaft Position Sensor ................................................................................... 185

V. Camshaft phase sensor.......................................................................................... 188

VI. Oxygen sensor ........................................................................................................ 191

VII. Fuel Injector (INJ) .................................................................................................... 194

VIII. Knock sensor........................................................................................................... 195

IX. Air-conditioning switch and relay ......................................................................... 197

X. Canister solenoid valve .......................................................................................... 198

XI. Ignition coil .............................................................................................................. 199

XII. Electric Fuel Pump.................................................................................................. 201

XIII. Electronic Control Module (ECM) of Engine ........................................................ 203

Section IV Trouble Diagnosis Procedures for Engine Control System ............206

I. Diagnosis with DTC ................................................................................................ 206

II. Diagnosis by Trouble Phenomena ........................................................................ 226

Maintenance Manual for J2 Sedan Mechanical Part of Engine

33

Chapter I Mechanical Part of Engine

Section I Engine Body

I. General Precautions

1. Precautions on Discharging Engine Coolant

Discharge coolant after engine has cooled down.

2. Precautions on Disconnecting Fuel Pipeline

1) Before the operation, ensure that the operating area is free of objects which may cause combustion

or sparks.

2) Disconnect the piping, plug openings to prevent leakage of fuel.

3. Precautions on Dismantlement and Disassembly

1) Use special tools as required in Instruction. Always operate safely; any forcible operations and

operations other than that specified in Instructions are forbidden.

2) Take particular care not to damage the matching face or the sliding face.

3) Use the adhesive tape or equivalent to cover the opening of engine system so as to prevent the entry

of foreign bodies, if necessary.

4) For the purpose of troubleshooting and reassembly, methodically mark and neaten the disassembled

parts.

5) When loosening the bolts and nuts, follow this basic principle: “outmost ones first, diagonal ones

second, and so on”. Conduct the operation in compliance with the loosening sequence, if specified.

4. Precautions on Check, Repair and Replacement

Thoroughly check the parts before repair or replacement. Check the substitutive parts by the same

means, and then replace as required.

5. Precautions on Assembly and Installation

1) Use the torque spanner to tighten the nuts and bolts.

2) When tightening the nuts and bolts, follow this basic principle: screw up the central nuts and bolts

with the same torque in steps, and then carry out the same operation with the internal and external

diagonal ones. Perform the operation in accordance with the tightening sequence, if it is specified.

3) Replace gaskets, oil seal or O-ring with new ones.

4) Thoroughly rinse, clean and dry every part. Carefully check the engine oil pipeline or engine

coolant pipeline for obstruction.

5) Never damage the sliding face and the matching face. Completely eliminate the foreign bodies such

as cloth scraps or the dust. Before assembly, paste the sliding face with engine oil.

6) When refilling engine coolant after draining completely, release air from the pipes at first.

7) After repair, start the engine and run with high speed to check for any leakage of the engine coolant,

fuel, engine oil and exhaust gas.


34

6. Parts Needed to Be Tightened with Specified Angle

1) Use the angle spanner to finally screw up following engine parts:

- Cylinder head bolt

- Bolt of main bearing cap

- Connecting rod bolt

2) Please follow the specified tightening methods.

3) Make sure that the surfaces of threads and pedestal are clean and coated with engine oil.

II. Precautions on Sealant

1. Removal of Sealant

After dismounting fixing nuts and bolts, use the

scraper to detach the matching faces and remove

old sealant.

Attention:

Do not damage the matching faces.

Insert the scraper, and then knock its side

to slide it as shown in the figure.

For the positions where it is difficult to use

scraper, lightly knock the parts to dismount

them with a plastic hammer.

If you have no choice but to use the tools

such as a screwdriver, be careful not to

damage the matching faces.

2. Application Steps of Sealant

1) Remove the attached old sealant from the

application and matching faces of liner with

scraper.

Attention:

Thoroughly remove the old sealant from

the groove on surfaces, fixing bolts and bolt

holes where the sealant was applied.

2) Wipe sealant surface and matching surface clean with a special cleaner, remove water drops, grease

and foreign substances.

JAC-T1F017

Fig.1.1.001

Fig.1.1.002

Slide Knock

Scraper


35

3) Position sealant with the specified size.

Put the sealant into the groove for it (if any).

Generally, the sealant is put inside the bolt hole; however, it is occasionally put outside the bolt

hole.

Install the matching part in a certain period of time after applying sealant.

Eliminate any dirt from the sealant.

Do not re-tighten the bolts or nuts after installation in order to avoid failures of bolts or nuts.

Add engine oil and coolant 30min after the installation has been finished.

Attention:

Conduct the operation in accordance with the instructions specified in this manual.

Fig.1.1.003


36

III. Preparation

1. Tools for Maintenance

List of Special Tools

No. Tool Appearance Code Description

1 End forked clamp

Fix camshaft

timing

sprocket

2 Pin

JAC-T1D001

Used together

with the end

forked clamp

3 Locating tool for

piston pin

Used to

install and

dismantle the

piston pin

4 Guide sleeve

JAC-T1F005

Used together

with the

locating tool

for piston pin

5 Flywheel chock

JAC-T1F011 Used to fix

the flywheel

6 Valve spring

compressor

JAC-T1F012

Used to

compress the

valve spring

Install valve

cotter


37

7 Oxygen sensor

socket

JAC-T1F015

Used to install

and dismantle

the oxygen

sensor

8 Dismantlement

tool for oil pan

JAC-T1F017

Used to

dismantle the

oil pan

9 Installer for

valve oil seal

JAC-T3F001

Used to install

the valve oil

seal

11

Guide for front

oil seal of

crankshaft

JAC-T3F003

Functioning as

a guide during

the installation

of front oil seal

of crankshaft

12

Installer for front

oil seal of

crankshaft

JAC-T3F004

Used to install

the front oil

seal of engine

crankshaft

13

Installer for rear

oil seal of

crankshaft

JAC-T3F005

Used to install

the rear oil seal

of crankshaft


38

2. List of Auxiliary Materials for Assembling Engine

List of Auxiliary Materials for Assembling Engine

No. Name Application Specification and Grade

1 Engine

oil Used during filling and assembly

Factory filled oil: SAE10W-30

Ambient temperature: -25-35

User must select the appropriate oil

according to the local temperature

Quality level: SJ or above

2 Silica

gel

Engine oil pump, water pump, oil pan

and rear oil seal housing of crankshaft LT5699 or equivalent

3 Sealant Oil pressure switch, draining screw plug

and flywheel bolt LT243 or equivalent

4 Sealant Coolant temperature sensor and water

temperature alarm switch LT648 or equivalent

5 Petrol 93# unleaded petrol or above

6 Sealant Stud bolt LT271 or equivalent

3. List of Auxiliary Materials for Assembling Cylinder head

List of Auxiliary Materials for Assembling Cylinder head

No. Name Present Material and Model Assembly Position

1 Engine oil

5W-30 (winter) 15W-40

(summer),with SJ-class quality

level and above

Valve head, camshaft and camshaft oil seal

2 Sealant LT271 or equivalent Stud bolt

3 Sealant LT962T or equivalent Guide sleeve of spark plug, bowl patch of

cylinder body/cover, connecting pipe nozzle


39

IV. Engine Assembly

1. Precautions on Installation and Dismantlement

Caution:

Operation in violation of the following instructions may incur personal injury!

Park the vehicle on flat and firm ground.

Attention:

Always pay attention to safe operation, and do not conduct any forcible operations or

operations other than that specified in Instructions.

Do not start before the exhaust system and engine coolant have completely cooled down.

If the necessary items or operations are not mentioned in the sections of Engine, see relevant

chapters.

Use the specified lifting points all the time and select appropriate lifters according conditions.

2. Preparation for Dismounting Engine and Transmission Assembly

1) General

Dismount the engine and transmission assembly from the vehicle, and then detach the engine from

transmission.

2) Preparation

① Discharge the engine coolant from the radiator. See “Change Engine Coolant”.

② Discharge the engine oil, transmission oil and clutch oil. See "Engine Oil", “Transmission Oil” and

“Clutch Pipeline”.

③ Collect the refrigerant in AC pipeline.

Attention:

Perform this step after the engine has cooled down.

Do not spill engine cooling fluid or brake fluid to the drive belt.

④ Dismount the following parts:

Engine trimming cover. See “Intake Manifold”.

Front wheels and tyres. See “Wheels and Tyres”.

Engine deflectors (left and right).

Air duct and air filter assembly. See “Air Duct”.

Battery, battery base and base support. See “Battery”.

Radiator assembly and radiator fan. See “Radiator”.


40

3. Dismantlement of Related Elements in Engine Compartment

① Disconnect the following pipelines and put them aside.

Attention:

Use plugs to prevent leakage when disconnecting the pipelines.

Inlet pipe of fuel injector. See “Fuel Injector”.

Vacuum hose of braking vacuum booster on engine side. See “Braking Vacuum Booster”.

PVC hose. See “Fuel Evaporation Control System”.

Oil inlet pipe joint of clutch. See “Hydraulic Pipeline of Clutch”.

Low and high-pressure pipes of air compressor. See “Air Compressor”.

② Remove the brake fluid reservoir.

③ Remove the accelerator cable.

④ Disconnect the wire harness connectors and buckles of the following parts and then take them

away:

Oxygen sensor

Engine coolant temperature sensor

Crankshaft position sensor

Camshaft position sensor

Speed sensor

Throttle opening sensor

Absolute intake pressure sensor

Ignition coil

Fuel injector

Knock sensor

Generator

Starter

Air conditioner switch

4. Dismantlement of Components of Chassis

① Dismount the front drive shaft. See “Front Drive Shaft”.

② Remove the front exhaust pipe. Please refer to “Exhaust System”.

③ Dismount the engine supporting beam. See “Engine Supporting Beam”.

5. Dismantlement

① Attach the lifting device hook to the hanging lug of the engine


41

② Lift the engine and fix it in place.

③ Use the manual lifting stand or equivalent to firmly support the bottom of engine and transmission

assembly; adjust the lifting tension.

Attention:

A soft pad may be placed on the supporting surface so as to ensure a totally stable state.

④ Detach left, right, front and rear suspensions of engine. See “Engine Suspension”.

⑤ Carefully lower the engine and transmission assembly. Be aware of following items during

operation:

Make sure that the work will not affect the vehicle.

Make sure that all connecting parts have been disconnected.

In order to avoid falling due to changes of vehicle gravity, use the jack to support the rear lifting

point.

6. Detachment

① Remove A/C compressor assembly from the engine and transmission assembly.

② Dismount starter. See “Starter”.

③ Lift engine and transmission assembly with specified lifter, and then detach them.

Attention:

Before lifting, check whether each connection wiring harness has been disconnected.

7. Installation

Be aware of following items to install with steps contrary to dismantlement.

1) Do not damage the soft pad of engine suspension. Meantime, avoid spilling engine oil onto the soft

pad.

2) Make sure that all engine suspensions have been properly fixed. Then, tighten the nuts and bolts.

8. Check after Installation

1) Check for any leakage.

The steps for checking oil and fluid leakage, lubricating oil leakage and the exhaust leakage are as

follows:

Fig.1.1.004

Fig.1.1.005


42

Before starting engine, check oil and fluid levels (including engine oil and coolant). Refill to

specified level as required..

Check for fuel leakage with following steps：

- With ignition switch turned to the “ON” position, check whether there is fuel leakage at the

connecting positions.

- With engine started, recheck whether there is fuel leakage at the connecting positions during engine

increasing.

During running of engine, check for any abnormal noise and/or vibration.

With engine warmed up, verify that there are no leakage of fuel, exhaust gas or other oil and liquid

(including engine coolant and oil).

Bleed air and replenish by using specified ports and hoses.

After engine cooled down, recheck oil and liquid levels (including engine oil and coolant). If

necessary, refill them to the specified levels.

2) General of Check Items

List of Leakage Check Items

Item Before Startup During Engine

Operation

After Engine

Stopped

Engine coolant Level Leakage Level

Engine oil Level Leakage Level

Transmission oil, brake fluid, and clutch fluid Level Leakage Level

Fuel Leakage Leakage Leakage

Exhaust — Leakage —


43

V. Drive Belt

1. Check Drive Belt

Warnings:

Be sure to operate only when engine stopped.

1) Check belt for aging, crack, wear and oil stain. Replace as required.

2) Check the belt tension at the mid-point between pulleys.

Inspection should be conducted with cold state of engine or when it has been stopped for at least

30min.

Tension range - Generator belt: 500±50N. Please be noted that the experience equation for

tensioning force of reused belt is as below: Tensioning force for new belt * 1.2/1.5

Adjust if tension is out of range.

Attention:

When checking belt tension after installation, firstly to adjust tension to specified value. Then

revolve the crankshaft for more than two laps to re-adjust in order to avoid tension between

pulleys changes.

2. Adjustment of Tension

List of Tension Adjustment

Part Method

Generator belt Screw adjusting bolt of generator

Attention:

After replacing with the new belt, adjust the tension so as to meet the requirements

When installing the belt, ensure the proper engagement with the belt pulley groove.

Do not splash the engine oil or engine coolant onto the belt.

Do not over wind or bend belt; for worn belt, pay attention to mounting direction.


44

3. Generator Belt

1) Loosen the generator adjusting nuts and supporting nuts. Then adjust the tension by using the

adjusting bolt.

2) Tighten generator adjusting and supporting nuts.

Tightening torque: Generator adjusting nuts: 22.5 ± 2.5 Nm

Generator supporting nuts: 47±5 N.m

4. Dismantlement of Drive Belt

1) Completely loosen the alternator belt as per the instructions in “Tension Adjustment”.

2) Remove the alternator belt.

5. Installation of Drive Belt

1) Mount the belt onto the pulley with steps contrary to dismantlement.

Attention:

Make sure that the belt has properly engaged with the groove of pulley.

Make sure that no engine oil or coolant splashed onto any belt or pulley groove.

2) Verify that the tension of every belt is within the standard range. See “Inspection of Drive Belt”.

Fig. 1.1.006 Fig. 1.1.007


45

VI. Air Filter and Air Duct

1. Parts

Diagram of Positions

2. Intake Pipe

1) Dismantlement

① Remove the fastening bolts and clamps of

front intake pipe and remove the front intake

pipe assembly.

Tightening torque: 17-19 N·m

② Loosen the lock clips from the air cleaner

upper cover.

Fig. 1.1.009

Fig. 1.1.008


46

③ Disconnect the locking clamp of intake hose, and then take off upper cover and intake hose.


④ Dismount the fixing bolt of air filter base, and

then take down the base.


2) Check after Dismantlement

Check whether there is any crack or wearing on the air duct assembly. If any, replace.

3) Installation


Attention:

Properly mount every joint and tighten the clamp.

3. Replacement of Air Filter element

1) Dismantlement

① Loosen the lock clips of air cleaner upper

cover and lift the upper cover.

Fig. 1.1.012

Fig. 1.1.011

Fig. 1.1.013

Fig. 1.1.010


47

② Dismount air filter element.


Periodically clean or replace the filter element with recommended period. See “Periodical

Maintenance”.

Blow the filter element from its back side with compressed air, till nothing is blown off.

3) Installation


VII. Intake Manifold and Exhaust Manifold

Decomposition Diagram of Intake and Exhaust Manifolds

1. Intake Manifold

1) Dismantlement

Caution:

Do not discharge the engine coolant when the engine is hot, otherwise you would be scalded.

Fig. 1.1.014


48

① Discharge the engine coolant. See “Engine Coolant”.

② Dismount the engine trimming cover.


③ Dismount the air filter assembly. See “Air filter Assembly”.

④ Disconnect the wire harness connectors of the following parts:


Fuel injector

Throttle position sensor

Carbon canister control solenoid

Accelerator cable

⑤ Disconnect the following hose joints:

Water hose joint (insert a plug to prevent the engine coolant leakage)

PCV hose

Vacuum hose of braking vacuum booster on intake manifold side

Vacuum hose on carbon canister solenoid side

Small circulating water hose for throttle valve body

⑥ Remove the fastening bolts of throttle body and

remove the throttle body assembly.

⑦ Dismount the fuel injector assembly. See “Fuel

Injector”.

Tightening torque: 18.4±1.4 N·m

Fig. 1.1.015

Fig. 1.1.016


49

⑧ Dismount the supporting bracket of intake manifold

and engine cylinder body.


⑨ Dismount the fixing bolt and nut of intake manifold.

Tightening torque: 18±1.0 N·m

⑩ Take off the intake manifold.


Check whether there is any crack or other damage on intake manifold and whether the matching face is

distorted. If this is the case, repair or replace the intake manifold. Check for any abnormal condition of

rubber rings.

3) Installation

Install with steps contrary to the dismantlement.

Attention:

Do not reuse the non-reusable parts.

Before starting the engine, check the level of engine coolant. If the level is lower, refill engine

coolant as specified.

Carry out the following steps to check whether fuel leakage is present.

———— With ignition switch turned to the “ON” position, check whether there is fuel leakage at the

connecting positions.

———— With engine started, recheck whether there is fuel leakage at the connecting positions during

engine increasing.

With engine warmed up, verify that there is no fuel and/or coolant leakage.

After engine cooled down, recheck the level of engine coolant. Refill to specified level as required.

2. Exhaust Manifold

1) Dismantlement

Fig. 1.1.017

Fig. 1.1.018


50

Caution:

Perform this operation after the exhaust system has completely cooled down.

① Disconnect the wire harness connectors of front

oxygen sensor. Special tools should be used if

necessary.


Attention:

Do not damage the oxygen sensor.

It is forbidden to use any oxygen sensor which has dropped to the hard ground from a height

above 0.5m. Such an oxygen sensor should be replaced.

② Unscrew the fixing bolt for heat shield of exhaust

manifold, and then take off heat shield.


④ Unscrew bracket bolt to remove the exhaust manifold

bracket.


⑤ Unscrew fixing bolt to remove the exhaust manifold.

Tightening torque: M8 35±2 N·m

Fig. 1.1.020

Fig. 1.1.019

Fig. 1.1.021

Fig. 1.1.022


51


Check whether the matching face of exhaust manifold is distorted.

3) Installation

Install with steps contrary to the dismantlement.

Attention:

Do not reuse the non-reusable parts.

Do not excessively tighten oxygen sensor, otherwise it may be damaged.

VIII. Exhaust System

1. Parts

Diagram of Exhaust System

1- Rear muffler; 2- Lug; 3- Front muffler; 4- Front exhaust pipe; 5-Three-element Catalytic Converter;

6- Bellow; 7-Rear oxygen sensor

2. Inspection of Exhaust System

Check whether the exhaust pipe, the three-way catalytic converter, the muffler and the fixing devices are

properly installed and whether there is any leakage, crack, damage or aging.

Repair or replace the damaged part as required.

3. Dismantlement and Installation

Attention:

Do not have you hand cut by the edge of heat shield.

Do use original exhaust system parts or equivalent products.

Perform the operation after the exhaust system has completely cooled down, for the temperature of

exhaust system remains hot when the engine has just stopped.

1) Dismantlement

Disconnect every joint and fixed part.

2

3

4

6

5

7

1


52

2) Installation



Replace the exhaust pipe gasket when reassembling the exhaust system each time.

Repair or replace the seriously distorted heat shield. Eliminate the accumulations from the heat

shield.

When install the heat shield, try to avoid wide clearance or blockage and intervention between the

heat shield and each exhaust pipe.

Eliminate the sediments from the sealed face of each joint. Such joints should be firmly connected

to avoid gas leakage.

Pre-tighten the fixing nuts and bolts on exhaust manifold side and those on vehicle side. Check

whether there is any intervention between parts, and then tighten the parts to specified torque.

When install the fixing rubber, avoid excessive upward/downward and leftward/rightward twist or

stretch.

3) Check after Installation

Verify clearance between rear muffler and rear bumper.

WIth engine running, check the connecting position of exhaust pipe for air leakage and abnormal

noise.

Ensure that the fixing support and the fixing rubber have been properly mounted. Do not subject

them to excessive force. Improper installation may result in considerable noise and shake.


53

IX. Timing sprocket mechanism

1. Parts

Timing sprocket mechanism diagram

1 – Timing chain 2 – Movable rail bolt subassembly 4. Movable rail subassembly

5 – Automatic tensioner bolt 5 – Automatic tensioner 6 – Bolt 7 – Balance shaft front cover plate

8 – Balance shaft chain wheel fastening bolt 9 – Balance shaft chain wheel 10 – Secondary chain

11 – Balance shaft idler gear 12 – Secondary tensioner 13 – Secondary tensioner torsion spring

14 – Fixed gauge subassembly 15 – Fixed gauge bolt subassembly

2. Dismantlement and Installation of Timing

chain

1) Dismantlement

a) Remove the water pump pulley and tensioner

fastening bolts.

Tightening torque: Water pump pulley bolts:

7~8.2N.m

Tensioner bolts: 40~58N.m

Fig. 1.1.023

Balance shaft gear


54

Note: It is permissible to perform the

dismantlement by means of the friction force of

drive belt before drive belt is removed.

b) Dismantle drive belt to check whether the

drive belt has wearing, aging, cracking, etc.;

if any, replace drive belt.

c) Dismantle oil gauge assembly

Tightening torque: 7-8.2 N·m

d) Dismantle damping wheel


e) Remove the alternator bracket.

f) Dismantle oil pan and cylinder head cover

Attention: Only when oil pan and cylinder head

cover are disassembled can the oil pump

assembly be dismantled.

Remove the cylinder head shield as per the

illustrated sequence.

Fig. 1.1.024

Fig. 1.1.025

Fig. 1.1.026

Fig. 1.1.027

Tightening sequence for bolts of cylinder head shield


55

g) Dismantle oil pump assembly

h) Check timing

Check the timing point shown in the diagram for compliance.

Fig. 1.1.028

Timing mark of primary chain

Timing mark of secondary chain

Timing mark of secondary chain

Timing mark for crankshaft chain wheel

Timing mark for balance shaft chain wheel

Timing mark of primary chain

Timing mark for camshaft chain wheel


56

i) Dismantle tensioner and set/dynamic tracks of

the automatic timing chain. Check for any

abnormalities.

Tightening torque: Automatic tensioner: 9 -

11 N • m

Set track: 10-12 N·m

Dynamic track: 19-28 N·m

j) Dismantle exhaust camshaft sprocket bolt

Tightening torque: 88±10 N·m

k) Remove t he bolts of intake cam chain wheel


l) Remove the rear end cap of balance shaft and

secure the anti-rotation device of balance

shaft on the tail of the balance shaft.

Tightening torque for rear end cap of balance

shaft: 7.6±0.6 N·m

Fig. 1.1.029

Fig. 1.1.031

Fig. 1.1.030


57

m) Remove the bolts of secondary chain

tensioner and remove the secondary chain

tensioner.


n) Remove the bolts of balance shaft chain wheel

and remove the balance shaft chain wheel.


2） Installation

Reverse the above steps for installation. Be aware of timing and tightening torque during installation.

Fig.1.1.033

Fig.1.1.034


58

X. Camshaft and balance shaft assembly

1. Parts

Breakdown diagram for camshaft and balance shaft

1 – Intake camshaft subassembly 2 – Intake camshaft chain wheel 3 – Chain wheel bolts

4 – Exhaust camshaft chain wheel 5 – Exhaust camshaft subassembly 6 – Mechanical tappet

7 – Balance shaft retaining bolt 8 – Balance shaft gear 9 – Balance shaft

10 – Balance shaft rear end cap gasket 11 – Balance shaft rear end cap

12 – Balance shaft rear end cap bolts

2. Disassembly and installation

1） Disassembly of camshaft

① Remove cylinder cover. See "Intake Manifold."

② Remove high-voltage ignition coil. See "Ignition Coil."

③ Disconnect PCV hose and air hose of respirator.

④ Remove the cylinder head cover from the cylinder head.

⑤ Remove camshaft timing sprocket. Seethe "timing sprocket body."

⑥ Remove camshaft position sensor from rear end of the cylinder head.

Tightening torque: 9 - 11 N • m


59

Attention:

Handle with care to avoid collision or damage.

⑦ Remove the camshaft from cylinder head.

2） Disassembly of balance shaft

On the basis of above-mentioned disassembly

procedure of camshaft, proceed as below:

Remove the bolts of balance shaft front end

cap and remove the balance shaft front end

cap.

① Tightening torque for balance shaft front end

cap: 7.6±0.5N.m

② Remove the balance shaft idler gear, remove

the bolts of balance shaft front gear, and

remove the balance shaft gear.

Tightening torque for bolts of balance shaft

front gear: 23.5±4.5N.m

③ Remove the bolts of exhaust bracket II and

balance shaft side cover and remove the

balance shaft.

Tightening torque for bolts of cover:

7.6±0.6N.m

Fastening bolts for exhaust pipe bracket II:

22.5±2.5N.m

Fig.1.1.037

Fig.1.1.036

Fig.1.1.035


60

3） Inspection after removal

① Camshaft

Measuring camshaft base circle diameter and

the maximum lifting strokes of intake and

exhaust.

Base circle diameter: 36mm

Maximum lifting stroke of intake：8.7054mm

Maximum lifting stroke of exhaust ：

8.2836mm

If specified value is exceeded, replace the

camshaft.

② Mechanical tappet

Measure the top thickness of the mechanical

tappet

Measurement should be within: 2.70 ～

2.30mm

4） Installation

Assembly of camshaft machenism: All parts camshaft assembly should be assembled according to

grouped drawings.

① The mechanical tappet at the intake side will be grouped and assembled as per the following table

to ensure the intake valve clearance.

Distance between intake camshaft base circle

and valve tappet L1

Top end thickness of

mechanical tappet

Mechanical tappet

label

Valve clearance

(mm)

2.91＜L1≤2.93 2.70 270 0.19-0.25

2.93＜L1≤2.95 2.72 272 0.19-0.25

2.95＜L1≤2.97 2.74 274 0.19-0.25

2.97＜L1≤2.99 2.76 276 0.19-0.25

2.99＜L1≤3.01 2.78 278 0.19-0.25

3.01＜L1≤3.03 2.80 280 0.19-0.25

3.03＜L1≤3.05 2.82 282 0.19-0.25

3.05＜L1≤3.07 2.84 284 0.19-0.25

3.07＜L1≤3.09 2.86 286 0.19-0.25

3.09＜L1≤3.11 2.88 288 0.19-0.25

3.11＜L1≤3.13 2.90 290 0.19-0.25

Fig.1.1.039

Fig.1.1.038


61

Distance between intake camshaft base circle

and valve tappet L1


mechanical tappet

Mechanical tappet

label

Valve clearance

(mm)

3.13＜L1≤3.15 2.92 292 0.19-0.25

3.15＜L1≤3.17 2.94 294 0.19-0.25

3.17＜L1≤3.19 2.96 296 0.19-0.25

3.19＜L1≤3.21 2.98 298 0.19-0.25

3.21＜L1≤3.23 3.00 300 0.19-0.25

3.23＜L1≤3.25 3.02 302 0.19-0.25

3.25＜L1≤3.27 3.04 304 0.19-0.25

3.27＜L1≤3.29 3.06 306 0.19-0.25

3.29＜L1≤3.31 3.08 308 0.19-0.25

3.31＜L1≤3.33 3.10 310 0.19-0.25

3.33＜L1≤3.35 3.12 312 0.19-0.25

3.35＜L1≤3.37 3.14 314 0.19-0.25

3.37＜L1≤3.39 3.16 316 0.19-0.25

3.39＜L1≤3.41 3.18 318 0.19-0.25

3.41＜L1≤3.43 3.20 320 0.19-0.25

3.43＜L1≤3.45 3.22 322 0.19-0.25

3.45＜L1≤3.47 3.24 324 0.19-0.25

3.47＜L1≤3.49 3.26 326 0.19-0.25

3.49＜L1≤3.51 3.28 328 0.19-0.25

3.51＜L1≤3.53 3.30 330 0.19-0.25

Table: Distance between intake camshaft base circle and top of valve tappet, top end thickness of the

mechanical tappet grouping and assembly


62

② The mechanical tappet at the exhaust side will be grouped and assembled as per the following table

to ensure the intake valve clearance.

Distance between exhaust camshaft base circle

and valve tappet L2


mechanical tappet

Mechanical

tappet label

Valve clearance

(mm)

2.99＜L2≤3.01 2.70 270 0.27-0.33

3.01＜L2≤3.03 2.72 272 0.27-0.33

3.03＜L2≤3.05 2.74 274 0.27-0.33

3.05＜L2≤3.07 2.76 276 0.27-0.33

3.07＜L2≤3.09 2.78 278 0.27-0.33

3.09＜L2≤3.11 2.80 280 0.27-0.33

3.11＜L2≤3.13 2.82 282 0.27-0.33

3.13＜L2≤3.15 2.84 284 0.27-0.33

3.15＜L2≤3.17 2.86 286 0.27-0.33

3.17＜L2≤3.19 2.88 288 0.27-0.33

3.19＜L2≤3.21 2.90 290 0.27-0.33

3.21＜L2≤3.23 2.92 292 0.27-0.33

3.23＜L2≤3.25 2.94 294 0.27-0.33

3.25＜L2≤3.27 2.96 296 0.27-0.33

3.27＜L2≤3.29 2.98 298 0.27-0.33

3.29＜L2≤3.31 3.00 300 0.27-0.33

3.31＜L2≤3.33 3.02 302 0.27-0.33

3.33＜L2≤3.35 3.04 304 0.27-0.33

3.35＜L2≤3.37 3.06 306 0.27-0.33

3.37＜L2≤3.39 3.08 308 0.27-0.33

3.39＜L2≤3.41 3.10 310 0.27-0.33

3.41＜L2≤3.43 3.12 312 0.27-0.33

3.43＜L2≤3.45 3.14 314 0.27-0.33

3.45＜L2≤3.47 3.16 316 0.27-0.33

3.47＜L2≤3.49 3.18 318 0.27-0.33

3.49＜L2≤3.51 3.20 320 0.27-0.33

3.51＜L2≤3.53 3.22 322 0.27-0.33

3.53＜L2≤3.55 3.24 324 0.27-0.33

3.55＜L2≤3.57 3.26 326 0.27-0.33

3.57＜L2≤3.59 3.28 328 0.27-0.33

3.59＜L2≤3.61 3.30 330 0.27-0.33

Table: Distance between the exhaust camshaft base circle and top of valve tappet, top end thickness of

mechanical tappet assembly grouping and assembling


63

Installation precautions:

Mechanical tappet should be applied with proper amount of oil evenly; after the cylinder head is

assembled, it should turn flexibly without sticking or other abnormalities.

Before assembling camshaft, proper amount of oil should be evenly applied on each contact

surface; after the camshaft bearing bolt is tightened, the camshaft should turn flexibly without

sticking or other abnormalities; axial clearance should be: 0.05 - 0.15mm. (Measurement

location)

③ Install the camshaft position sensor.

Attention:

Apply a film of sealant to the flange of rear end cover.

Tighten the fixing bolt after the support has been fully mounted.

④ Install camshaft timing sprocket

⑤ Install the timing chain wheel of balance

shaft. During installation, notice to align the

timing mark of balance shaft.

Backlash of balance shaft gear: 0.06-0.12mm

Backlash of balance shaft idler gear:

0.08-0.14mm

⑥ Be aware of following items to install with steps contrary to dismantlement.

Before installing cylinder head cover, clear any sealant on cylinder head.

Make sure that cylinder head cover gasket is put into the installation slot.


Check for proper position of all parts installed.

Check the level of engine oil before starting the engine. If the engine oil is less than the required

volume, replenish to specified level.

With engine running, check for abnormal noise and vibration.

Be sure that there is no oil leakage after engine warmed-up thoroughly.

Recheck the level of engine oil with engine cooled down. Replenish the engine oil to the specified

level as required.

Fig.1.1.040

Timing mark of balance shaft gear and idler gear


64

XI. Cylinder head

1. On-vehicle Maintenance

1) Inspect the cylinder pressure:

① Thoroughly warm up the engine and then stop it.

② Release the fuel pressure. See “Release of Fuel Pressure”.

③ Disconnect the fuse of fuel pump, otherwise the fuel may be sprayed out during measurement.

④ Use special ignition coil and spark plug removal tool. See "Ignition Coil" and the "Spark Plug."

⑤ Dismantle engine trimming cover. See “Intake manifold”.

⑥ Install a cylinder pressure gauge (with joint) on the spark plug hole.

⑦ Push the accelerator pedal to the end, then turn the ignition switch to the “START” position to start

the engine. After the instrument finger appears stable, read compression pressure and engine speed.

Perform these steps to check other cylinders.

Standard pressure: 1200±100 kPa

Tolerable pressure difference between cylinders: ≤98kPa

Attention:

It is required to obtain the specified engine speed always by the battery which is fully

charged.

Inspect valve clearance and other relevant parts (such as valve, valve seat, piston, piston ring,

cylinder bore, cylinder head and gasket) if the compression pressure is less than the minimum

value. Repeat measurement of compression pressure after the check.

If the pressures in some cylinders are low, add some engine oil to the spark plug holes of such

cylinders and then inspect again.

The piston ring may be worn or damaged if the cylinder pressure rises after the engine oil is

added. Check the piston ring and replace if necessary.

The valve may have faulty if the compression pressure is still low after the adding of engine

oil. Check whether the valve is damaged. Replace the damaged valve or valve seat.

The cylinder gasket must be leaky if the compression pressures in two neighboring cylinders

are low and even keep low after adding engine oil. Replace cylinder gasket.

⑧ After inspection, remount the dismounted parts.

⑨ Start engine, confirm that the engine runs smoothly.


65

2. Parts

Diagram of Cylinder head


1) Dismantlement

① Discharge engine coolant and oil. See “Change Engine Coolant” and “Change Engine Oil”.

Attention:

Perform these steps after engine cooled down.

Do not splash engine coolant or oil onto the drive belt.

② Dismount the following elements and the relevant parts:

Engine trimming cover. See “Intake Manifold”.

Drive belt. See “Drive Belt”.

Cylinder head cover. See "Camshaft Assembly."

Intake manifold. See “Intake Manifold”.

Exhaust manifold. See “Exhaust Manifold”.

Oil gauge tube.

Oil pump body assembly and timing mechanism. See the "Timing Sprocket Mechanism."

③ Loosen the cylinder head bolts with special tool.

④ Remove the cylinder gasket.


66


① Cylinder head Bolt

Measure the length of cylinder head bolt.

Limit: 143.5±0.7mm. Replace the cylinder head bolt if this Limit is exceeded.

② Cylinder head

Check whether there are cracks or other damages on the cylinder head.

Check whether there is any blockage in the coolant gallery and oil passage. If any, clean the coolant

gallery and oil passage.

Check planeness of cylinder head.

Note: Check the planeness of cylinder body as well when performing this check.

a. Wipe off the engine oil from the cylinder head, remove any sealant and the carbon deposit.

Attention:

Be careful to prevent impurities from falling into coolant gallery and oil passage of cylinder

head.

b. Measure the planeness in six directions at

several positions on bottom surface of

cylinder head.

Standard value: below 0.03mm

Height of cylinder head (new): 113±0.1mm

If the the standard value is exceeded, grind or

replace the cylinder head according to the

specification.

Attention:

The total grindable margin of matching surface between cylinder head and cylinder body

should not be greater than 0.2mm.

3) Installation

① Install new cylinder gasket.

② Follow the numerical order as shown in the

diagram to tighten the cylinder head bolt and

follow the given steps to install cylinder head.

A: Intake side

B: Exhaust side

: Front end of engine

a. Install washer.

Fig.1.1.042

Fig. 1.1.041


67

b. Apply a film of engine oil onto washer, which is at the threaded portion of bolt.

c. Tighten cylinder head bolts in sequence, until each bolt torque is 24.5 ± 2 N • m.

d. Fully unscrew bolts.

e. Tighten the bolts until the torque of each bolt is 24.5 ± 2N • m.

f. Paint marks on the bolt head and the cylinder

head (see Fig.1.1.040).

g. Screw each bolt for more 90° with to the

tightening sequence.

h. Re-tighten each bolt by 90°.

Attention:

When the two tightening angles are below

180 °, tightening performance can not be

assured; be sure to reach 180 ° when

tightening.

When the two tightening angles are above 184 °, completely loosen the bolt and re-tighten per

the initial sequence.

i. If the old cylinder head bolts are replaced during the maintenance, operation should be performed

in sequence from “a” to “h”.

j. If the old cylinder head bolts are not replaced during the maintenance, operation should be

performed in sequence “a, b, e, f, g and h”.

③ Then, perform the installation steps which are just contrary to dismantlement.


The steps for checking oil leakage, lubricant leakage and tail gas leakage are as following:

Before starting the engine, check the engine oil/coolant level. If the level is lower, replenish the

engine oil/coolant till the specified level is reached.

Perform the following steps to check whether the oil leakage occurs:

— Turn the ignition switch to the “ON” position (when engine is stopped). With the oil pressure

acting on the oil pipe, check whether there is fuel leakage at the joint.

— Start the engine. With the engine accelerating, recheck whether there is fuel leakage at the joint.

Run the engine to check whether the abnormal noise or vibration appears.

With engine warmed up completely, verify that there is no fuel leakage, tail gas leakage or any

oil/fluid (including engine oil and coolant) leakage.

After engine cooled down, recheck oil/fluid (including engine oil and engine coolant) level.

Replenish the oil/fluid to the specified level as required.

Fig.1.1.043

Painting Mark


68

XII. Valves

1. Parts

Diagram of Valve parts

1 - cylinder head bolts 2 - cylinder head bolt washer 3 - cylinder head assembly 4 - Cylinder

gasket 5 – intake valve cotter 6 - intake valve spring upper seat 7 - intake valve spring 8 - intake

valve

9 - exhaust valve cotter 10 - exhaust valve spring upper seat 11 - exhaust valve spring

12 - exhaust valve 13 - intake valve oil seal 14 - intake valve spring lower seat

15 - exhaust valve seal 16 - exhaust valve spring lower seat 17 - intake valve guide

18 - exhaust valve guide 19 -intake valve seat 20 - exhaust valve seat 21 - cylinder head

2. Disassembly and Assembly

1) Disassembly

① Dismount the spark plug with the special

socket.

② Dismount the valve cotter, valve spring and

spring seat.

Compress the valve spring with the special

Fig.1.1.044 JAC-T1F001


69

compressor.

Attention:

Pay attention to the position of upper dead

point of piston.

Label the dismounted valve, valve spring

and other parts, and write down their

corresponding cylinder numbers and

positions

Store the parts reliably.

③ Dismount the valve oil seal.

④ See “Replacement of Valve Seat” to replace

the valve seat, if required.

⑤ See “Valve Guide” to replace the valve guide,

if required.

2) Assembly

① Install valve guide if it has been dismounted. See “Valve Guide”.

② Install valve seat, if it has been dismounted. See “Valve Seat”.

③ Install valve oil seal.

a. Install the valve spring seat.

b. Install the new valve oil seal with the special

tool shown in Fig.1.1.044

Attention:

The valve oil seal should not be reused.

The valve oil seal must be installed with

the proper special tool.

④ Install valve.

⑤ Install valve spring.

Fig.1.1.045 JAC-T1F012

Fig.1.1.046

Fig1.1.047

JAC-T3F001


70

Note: The parts with paint mark should be installed upwards.

⑥ Install retaining seat for valve spring.

⑦ Install valve cotter.

Use the valve spring compressor during the installation.

After installation, lightly knock the edge of valve stem with a rubber hammer to check the

mounting condition.

⑧ Install spark plug with the spark plug socket.

3) Check after Disassembly

1. Valve

Check whether the contact between valve

surfaces is proper. Renew the surface of valve

seat if the contact is uneven or incomplete.

Inspect thickness of valve edge. Replace the

valve if the measurement is less than the

specified value.

For intake valve: 1.35-1.65mm，

For exhaust valve: 1.85±0.15mm

Inspect the total length of valve. Replace the valve if the measurement is less than specified value.

For intake valve: 89.51-90.01mm，

For exhaust valve: 90.69-91.19mm

2. Valve Spring

Check free height of valve spring. Replace the valve spring if the measurement is less than

specified value.

Check perpendicularity of valve spring. Replace the valve spring if the measurement is out of

limit.

Standard value: 2°

Limit: 4°

Fig.1.1.048

Fig.1.1.049

Good

Bad Bad

Contact (required to be at the center of

surface) Thickness of

edge


71

3. Valve guide

Check the gap between the valve guide and

the valve stem. Replace the corresponding

parts if the measurement is out of limit.

Valve guide

Standard value: 0.020-0.036mm

Limit: 0.10mm

Replacement of Valve guide

a. Push out the valve guide towards the cylinder side by the press.

b. Rebore mounting hole on the valve guide of cylinder head to make it match increased size of valve

guide to be installed.

Attention:

Do not install the valve guides with the same sizes of old ones. Re-boring mounting hole on

the valve guide of cylinder head

Outer diameter of valve guide:

For the hole with diameter of 10.655-10.665mm,

extend the size of valve guide by 0.05mm.





c. Press the valve guide till its protrusion height

reaches the specified value.

Standard value: 23.0mm

Attention:

Use cold pressing method to install valve guide from upper side of cylinder head. Check

whether there are cracks after press fitting.

After valve guide pressed in, insert a new valve to check for smooth sliding of valve.

4. Valve Seat

Check the valve protrusion height between the end face of valve stem and the surface of valve

spring seat. Replace the valve seat if the limit is exceeded.

Fig.1.1.050

Fig.1.1.051

Valve guide

Inner Diameter of Valve Conduit

Outer Diameter of Valve Stem

Protrusion Height


72

Standard values:

For intake valve: 53.21mm

For exhaust valve: 54.10mm

Limits:

For intake valve: 53.71mm

For exhaust valve: 54.60mm

Renew valve seat.

a. Before renewing the valve seat, check the clearance between valve guide and valve. Replace the

valve guide if necessary.

b. Resurfacing the valve seat by the proper special tool or the valve seat grinder till specified seat

surface width and angle are met.

c. After renewing the valve seat, grind the valve and the valve seat by the grinding cream. Then,

check the protrusion height of valve stem (refer to the above mentioned check steps of valve seat)

Replacement of Valve Seat

a. Cut away the replaced valve seat from its

inner side in order to decrease the wall

thickness. Then remove the valve seat.

b. Rebore the valve seat hole on cylinder head

till the hole matches the selected valve seat

with a extended diameter. See “Parameters

for Maintenance” for the detailed size.

c. Do not have the cylinder head hole scratched

by the valve seat cooled by the liquid

nitrogen before it is pressed.

d. Renew the valve seat till its width and angle

meet the specifications (see the operation

instruction of valve seat correction).

e. leak testing must be conducted for

disassembly of valve related components.

XIII. Cylinder Body Assembly

图图图图 1.1.052

Fig.1.1.053

Fig.1.1.054

End Face of Valve Stem

Valve Protrusion Height

Surface of Valve Spring Seat

Cut Away

Valve Seat Height

Inner Diameter of Extended Hole


73

1. Parts

Disassembly Diagram of Cylinder Body Assembly


1) Disassembly

① Dismount the engine assembly from the vehicle, and then detach the transmission from engine. See

“Engine Assembly” for detailed dismantlement steps.

③ Fix whole engine.

④ Discharge engine oil. See “Change Engine Oil”

⑤ Dismount following engine accessories. See relevant chapters for detailed dismantlement steps.

Drive belt

Alternator, compressor and relevant brackets

Intake and exhaust manifolds


74

Water pump and its components

Ignition coil

Cylinder cover, damping wheel, oil pan

Engine timing sprocket mechanism

⑥ Dismount the flywheel assembly. Fix the flywheel by the special tool to dismount the fixing bolt.

Tightening torque: For flywheel: 95-105N·m

Attention:

Fixing bolts should be loosened in the diagonal orders.

⑦ Disassemble knock sensor, crankshaft position sensor, oil pressure switch.

Tightening torque: Knock sensor: 16 - 24 N • m

Crankshaft position sensor: 7.8 - 9 N • m

Oil pressure switch: 8 - 12 N • m

Attention:

Do not drop or knock the sensor.

⑧ Remove crankshaft rear oil seal bracket

Tightening torque: 7.0-8.2N·m

Insert the screwdriver between the crankshaft and the rear oil seal housing to dismantle.

Attention:

Once dismounted, the rear oil seal must not be reused. It should be replaced by a new one.

⑨ Dismount the piston and connecting rod assembly:

Before dismounting the piston and connecting rod assembly, check the gap at the big end of connecting

rod. See “Check after Disassembly” below.

a. Rotate the crankshaft to place the journal side of crankshaft which is corresponding to the

connecting rod to be dismounted at the center of bottom.

b. Dismount the connecting rod cover.

Tightening torque: 13±1N·m + 90°-94°

Be aware that when tightening the "5Nm → 10Nm → 13Nm +45 ° +45 °" alternate methods should be

followed to tighten.

c. Push out the piston and connecting rod assembly from the cylinder body by the rubber hammer or

equivalent.

Attention:

Be careful not to damage the big bonnet and connecting rod fitting surface

Do not damage the cylinder wall and the crankshaft journal with the big end of the connecting


75

rod.

Maintain the connecting rod big end and the connecting rod body match sequentially and

maintain the connecting rod big end serial number in consistency

⑩ Dismount bearing shell from the connecting rod and the connecting rod cover.

Attention:

Identify their mounting positions, and properly place them to avoid confusion.

⑪ Dismount ring from the piston.

Check the side clearance of piston ring before dismounting. See “Check after Disassembly” below.

Attention:

Use the piston ring expander.

⑫ Dismount the piston ring from the connecting

rod with method below:

a. Insert the push rod (special tool) from the

front side with a arrow mark, and then install

the guide sleeve D.

b. With the front mark of piston face upwards,

install piston and connecting rod assembly on

the mounting base of piston pin (special tool).

c. Push out the piston ring by the press.

d. Detach the connecting rod from piston.

Attention:

After dismounting piston pin, place it

together with the piston pin and the

connecting rod.

It is forbidden to place the pistons, piston

pins and connecting rods of different

cylinders together.

⑬ Dismount the crankshaft bearing cap.

Before loosening the crankshaft bearing cap, measure axial clearance of crankshaft. See “Check after

Disassembly” below.

Fig.1.1.055

Fig.1.1.056

Piston Ring Expander

Push Rod

Guide Sleeve D

Base

Front Mark


76

Loosen the bolts of crankshaft bearing cap in the

following sequence.

Tightening torque: 35±2 N·m＋60°～64°

Be aware of the number and forward mark of

bearing cap.

During the dismantlement, it is allowable to jiggle

the crankshaft bearing cap forwards and

backwards by the bolts of crankshaft bearing cap.

See Fig.1.1.055.

⑭ Dismount the crankshaft.

2) Check after Disassembly

① Axial clearance of Crankshaft

Detection methods are as shown in the figure


If measurement is not within the standard range, replace the thrust washer and repeat measurement. If it

is still over limit, replace the crankshaft.

② Big End Clearance of Connecting Rod

Measure the gap between the connecting rod and

the crankshaft by using feeler gauge.


Limit: 0.4mm

If the limit is exceeded, replace the connecting rod

and measure again. Replace the crankshaft if

measurement is still out of the limit.

Fig.1.1.058

Fig.1.1.057

Fig.1.1.059

Fig.1.1.060


77

③ Side clearance of Piston Ring

Measure the side clearance between piston ring

and piston ring groove top land by the feeler

gauge.

Standard values:

For 1st piston ring, 0.03～0.07mm

For 2nd piston ring, 0.04～0.06mm

Limits:

For 1st piston ring, 0.1mm

For 2nd piston ring, 0.1mm

If the measurement exceeds the limit, replace the piston ring, and then remeasure the gap. Replace the

piston if the measurement is still out of the limit.

④ End Gap of Piston Ring

Ensure that the inner diameter of cylinder stays

within the specified range.

See "Cylindricality of Cylinder"

Lubricate the piston and the piston ring with new

engine oil, then insert the piston ring till the piston

reaches the middle part of cylinder, measure end

gap of piston ring by the feeler gauge.

Standard values:

For 1st piston ring, 0.15-0.30mm

For 2nd piston ring, 0.30-0.50mm

Limits:

For 1st piston ring, 0.8mm

For 2nd piston ring, 0.8mm

If the measurement exceeds the limit, replace the piston ring, and then measure again. Extend cylinder

bore through grinding and use the corresponding piston and piston ring if the measurement is still over

the limit.

⑤ Planeness of Cylinder Body

Remove any gasket material and eliminate the engine oil, sediment, carbon or other contaminants on

surface of cylinder body.

Fig.1.1.062

Fig.1.1.061

Piston Ring

Feeler Gauge

Good

Feeler Gauge

Bad

Feeler Gauge

Piston

Piston Ring

Piston Ring

Measured Point

Pressed and Fixed


78

Attention:

Be careful to prevent gasket materials from falling into the engine oil or coolant.

Measure planeness of cylinder body in different

directions at six positions using ruler and feeler gauge.

Standard values: below 0.05mm

Limits: below 0.1mm

If the limit is exceeded, replace cylinder body.

⑥ Cylindricality of Cylinder

Measure the cylinder degree at 6 different points per cylinder by using micrometer.

Standard values:

For cylinder bore: 75.0mm

For cylindricality: below 0.07mm

⑦ Diameter of Piston Skirt

Use outside micrometer to check whether the

piston skirt is distorted.

Standard values:74.973mm

⑧ Clearance between Piston and Cylinder Bore

Calculate per the actual measurement of piston skirt and cylinder bore.

(Gap) ＝ (inner diameter of cylinder) － (diameter of piston skirt)


If the calculated value exceeds the limit, replace piston and piston ring assembly.

⑨ Boring Cylinder

a. The piston with extended size to be used should be determined in accordance with the cylinder

which has the highest bore.

Pistons of the following extended sizes, i.e. 0.25mm, 0.50mm, 0.75mm and 1.00mm, are applicable.

b. Measure the diameter of piston to be used.

After boring cylinder, clearance between piston and cylinder bore must be within standard range. The

Fig.1.1.063

Fig.1.1.064

Feeler Gauge

Ruler

Dial Indicator


79

piston diameter should be measured at the position shown in Figure.

c. Calculate the boring size based on the piston diameter.

[Boring size] ＝ [outer diameter of piston] ＋ [clearance between piston and cylinder (0.02-0.04mm)]

－ [grinding margin (0.02mm)]

d. Boring each cylinder till it obtains the calculated boring size.

Attention:

To avoid the distortion due to heat during the boring course, bore the cylinders in following

sequence: Cylinder 2 → Cylinder 4 → Cylinder 1 → Cylinder 3

e. Grind the cylinder till it meets the final processing size (outer diameter of piston ＋ clearance

between piston and cylinder)

⑩ Diameter of Main Crankshaft Journal

Measure the main crankshaft journal by the outside micrometer.

Standard value: 48.0mm

If it exceeds the standard, please follow the rules of selection to replace.

⑪ Diameter of Main Journal of Connecting Rod

Measure the diameter of main journal of

connecting rod by using outside micrometer.

Standard values:43.0mm

Replace the connecting rod bearing shell if

measurement exceeds standard value.

⑫ Gap of Connecting Rod Bearing Shell

Note: Use the plastic divider to perform the

measurement.

a. Clean any engine oil from the connecting rod

journal and connecting rod bearing shell.

b. Put the plastic divider on the connecting rod

journal, and asset it to a length equal to

bearing shell width. The plastic divider must

be placed at the center of connecting rod

journal and be parallel with the axial line of

connecting rod.

c. Lightly put the connecting rod cover to

specified place, and screw the bolt to

specified torque.

d. Dismount the bolt, then take off the connecting rod cover slowly.

e. Measure the pressed portion of plastic divider at the widest point by the scale which is printed on

the plastic divider bag.

Fig.1.1.066

Fig.1.1.065 Dial Indicator


80

Standard value: 0.02 - 0.04mm + (0.01mm) expansion

Limit:0.1mm

⑬ Roundness and Cylindricality of Crankshaft

Measure sizes of each main crankshaft journal and

main connecting rod journal at four different

positions as shown in the figure.

The difference between “X” and “Y” of “A”

and “B” represents the roundness.

The difference between “A” and “B” of “X”

and “Y” represents the cylindricality.

Limits: For roundness: equal to or less than 0.05mm

For cylindricality: equal to or less than 0.05mm

Calibrate or replace the crankshaft if the measurements exceed the limits.

⑭ Clearance of Crankshaft

a. Wipe off oil from the crankshaft journal and the inner surface of bearing shell.

b. Mount the bearing shell.

c. Set the plastic divicer till its width equals to the width of bearing shell. Then put them on the

journal along the axial line of journal.

d. Lightly mount the crankshaft bearing shell cover, and screw the bolt till to specified torque.

e. Dismount the bolt and lightly take off the crankshaft bearing shell cover.

f. Measure the pressed portion of plastic divider at

the widest point by the scale which is printed on

the plastic wire gauge bag.

Standard values: 0.02-0.04mm

Limit:0.1mm

Attention:

The connecting rod journal and main

journal of crankshaft should be rolled but

needn't to be machined to the reduced size.

Fig.1.1.067

Fig.1.1.068

Fig.1.1.069

Plastic Wire Gauge

Round-angle Rolling Area


81

⑮ Flywheel

Check whether the flywheel and the signal disk are distorted or cracked.

Attention:

Do not disassemble the flywheel.

16 Crankshaft signal wheel

Check whether the crank signal wheel has

distortions, cracks and other anomalies.

Check whether the bolts are loose

3) Assembly

① Blow away any oil and coolant from the cylinder body, the cylinder bore and the crankcase.

Remove any foreign bodies.

Attention:

Use goggles to protect your eyes.

② Install the upper and lower main bearings shells.

Attention:

Select the bearing shells by using the identification marks of crankshaft (See the table below).

If the crankshaft can not be identified, measure the diameter of crankshaft, and then select

the corresponding bearing shell to match the crankshaft.

Crankshaft group marking

Main bearing

Hole group marking

1 2 3 4 5

0 (up / down) Black／Black Black／Yellow Black／Red Black／White Black／Purple

1 (up / down) Yellow／Black Yellow／

Yellow

Yellow／Red Yellow／

White Yellow／Purple

2(up / down) Red／Black Red／Yellow Red／Red Red／White Red／Purple

a. Remove any dust, dirt and oil from the matching surfaces of cylinder body and main bearing cap.

b. Install intermediate and upper bearing shells on the cylinder body

c. Be aware of direction of bearing shell during the installation.

Bearings shells with oil holes and slots should be installed at block side; other shells should be

installed at the main bearing cap side.

For installation of bearings, clean before installation. Please apply engine oil to the bearing surface.

Do not use oil on the back, but to thoroughly clean it.

During installation, align the extrusion on bearing shell with the cut of cylinder body and main

bearing cap.

Fig.1.1.070


82

③ Add oil to bearing surface

Install crankshaft on cylinder block. When rotating the crankshaft by hand, check whether the rotation

of crankshaft is smooth.

④ Install main bearing cap.

The main bearing cap can be identified through

mark.

Install the main bearing cap starting from the

front of the engine according to the ordering

numbers.

Arrow must point to engine front.

⑤ Tighten the bolts of main bearing cap to

standard torque.

a. Apply new engine oil onto the thread and fixing surface of bolts of main bearing cap.

b. Tighten bolts for main bearing cap in steps.

Tightening torque: 35±2N·m

Screw all bearing cap bolts by 60-64° clockwise.

After installation of bolts of main bearing cap, verify that the crankshaft can be rotated smoothly by

hand.

Check the axial clearance of crankshaft. See “Axial clearance of Crankshaft”.

⑥ Install piston onto the connecting rod with

following instructions.

a. Measure the following lengths (See right

Figure).

A： Distance from piston flange to piston flange

outside

B： Distance from piston flange to piston flange

inside

C： Length of piston pin.

D： Thickness of small end of connecting rod.

b. Introduce the measurements into following

formula:

L = [(A-C)-(B-D)]／2

c. Insert push rod (special tool) into the piston pin, and then install guide sleeve.

d. When mounting the piston and the connecting rod, keep the front marks at same side.

e. Apply the engine oil onto the outer circle of piston pin.

f. Starting from the guide sleeve, press the guide sleeve, piston pin and push rod into the piston front

Fig.1.1.072

Fig.1.1.071

Pis

ton

Pin

Pis

ton

Connecting Rod


83

mark side.

g. Screw in the guide sleeves, clearance between

the two sleeves should be 3mm plus the

calculated L in Step 2.

h. With the front mark facing downwards,

install piston and connecting rod on mounting

base of piston pin.

i. Install piston pin by the press.

Attention:

If the pressing load exceeds specified value, replace the piston pin and piston assembly and/or

the connecting rod.

Standard value: 108±54N·m

⑦ Install piston pin.

Attention:

When mounting the piston ring, do not damage the piston.

Do not damage the piston ring due to the excessive expansion.

a. Install oil ring

a) Install oil ring lining ring into the piston ring groove. Then install the upper and lower blades.

Attention:

Lining ring and blade can be installed in two directions。。。。 There is no difference between

upper and lower blades.

Lining ring and blade size coloring scheme.

Table of lining ring and blade size coloring scheme

Size Color

Standard Colorless

Extended by 0.50mm Blue

Extended by 1.00mm Yellow

b) To install the blade, install one end of blade into the groove (as shown in the diagram) before

pressing the other areas to place.

Attention:

Do install blades by using piston ring

expander, otherwise, they may break.

c) After installation of the blades, check whether

they can move smoothly in both directions.

Fig.1.1.073

Fig.1.1.074

Guide Sleeve B

Guide Sleeve A

Piston Ring Expander


84

b. Install first and second piston rings.

Install first and second piston rings with the identification marks facing upwards (on the piston top side)

by using expander.

Notes: Piston ring opening direction

⑧ Install bearing shell onto the connecting rod and the connecting rod cover.

Apply engine oil onto bearing surface of shells before installation. Do not use engine oil on the

back but to thoroughly clean it.

⑨ Install piston and connecting rod assembly onto the crankshaft.

Place the crankshaft journal which is corresponding to the connecting rod to be mounted at the just

center of bottom.

Apply sufficient engine oil onto cylinder bore, piston and crankshaft journal.

Align air ring opening with oil ring opening. See Fig.1.1.097.

Install piston rod assembly in corresponding cylinder according to marks on connecting rod.

Make sure that the front mark on piston top faces to timing belt, and then press the piston and

connecting rod assembly into the cylinder from the cylinder upside.

Schematic Diagram for Piston Ring Location

Opening direction of first gas ring Opening direction of combined oil ring lower blade

Opening direction of lining ring of combined oil ring

Opening direction of combined oil ring upper blade Opening direction of second gas ring

Engine front-end

Schematic Diagram for Piston Ring Location

Opening direction of first gas ring Opening direction of combined oil ring lower blade

Opening direction of lining ring of combined oil ring

Opening direction of second gas ring Opening direction of combined oil ring upper blade

Engine front-end


85

Make the piston ring with front mark facing

the front end of engine by the piston ring

compressor or other suitable tool, then install

piston ring onto piston head.

Attention:

Do not damage cylinder wall or crankshaft

journal by the big end of connecting rod.

Do not to damage big bonnet and

connecting rod fitting surface

⑩ Install connecting rod cover.

During installation, first use high pressure gas for

blowing the expansion sections.

When tightening connecting rod bolt, the order of

“5Nm→10Nm→13Nm+45°+45°”alternate

methods should be followed. After piston

connecting rod assembly is installed, verify that

clearance for the connecting rod big end is 0.10 -

0.30mm.

Attention:

Connecting rod bolts can only be used once..

Before installing nut, apply engine oil on its thread and seat.

⑪ Install rear oil seal housing of crankshaft with rear oil seal assemble to the cylinder block.

⑫ Installation of knock sensor, Hall sensors, oil pressure switch.

Attention:

Do not screw the nut when grasping the joint.

If the knock sensor is shocked, replace with a new one.

Note: Be sure that there is no foreign body at the matching surface of cylinder body or the back side of

knock sensor.

⑬ Be aware of following to install with steps contrary to dismantlement.

Flywheel

Alternately tighten bolts to specified torque.

Fig.1.1.075

Fig.1.1.076


86

XIV. Diagnosis of Common Troubles

Diagnosis List of Common Troubles

Trouble Possible Cause Resolution

The cylinder gasket is leaky. Replace cylinder gasket.

The piston ring is damaged or worn. Replace the piston ring.

The cylinder or the piston is worn. Repair or replace the piston or the

cylinder body.

Low cylinder

pressure

The valve seat is worn or damaged. Repair or replace the valve seat.

The volume of engine oil is insufficient. Check oil level.

The engine oil pressure sensor failed. Replace sensor.

The engine oil filter is blocked. Replace filter.

Oil pump rotor or cover damaged Replace.

The viscosity of engine oil is low. Check. Change oil as required.

The plunger of engine oil pressure switch is constantly

open.

Repair.

Low oil pressure

The bearing gap is high. Replace.

High engine oil

pressure

The plunger of engine oil pressure switch is constantly

closed.

Repair.

The engine supporting bolt loosened Tighten

The transmission mounting support loosened. Tighten

The engine support loosened Tighten

The heat shield for engine is damaged. Replace.

The engine support heat shield is damaged. Replace.

Engine quiver

The heat shield for transmission is damaged. Replace

The engine oil is thin (low oil pressure). Change oil. Noise of valve

The valve or the valve guide is damaged or worn. Replace.

The oil is insufficient. Check the level of engine oil.

The engine oil is thin (the oil pressure is low). Change oil.

Noise from

connecting rod

bearing shell and the

main bearing shell The bearing gap is wide. Check and then determine the cause.

The radiator or the radiating pipe is leaky. Repair or replace.

The water tank cover is not sealed. Tighten or replace the cover.

The thermostat is leaky. Replace the thermostat pad.

The radiator is leaky. Repair or replace.

Poor cooling

performance

The water pump is leaky. Replace.

Jam in radiator The coolant contains the impurities. Replace the coolant.

The water tank cover is not strictly sealed. Replace.

The cooling system is jammed. Rinse or replace.

High temperature of

coolant

The thermostat is at fault. Replace.


87

Trouble Possible Cause Resolution

The belt skids. Adjust or replace.

The water pump is at fault. Replace.

The sensor is at fault. Repair or replace.

The fan is at fault. Repair or replace.

The coolant is insufficient. Replenish

The thermostat is at fault. Replace. Low temperature of

coolant The sensor or the wire harness is at fault. Repair or replace.

The sensor or the starter is at fault. Repair or replace. Ineffective fan

The fan relay or the wire harness is damaged. Repair or replace.

The joint loosened. Tighten it

The exhaust pipe or the muffler is damaged. Repair or replace. Exhaust system leaks

Exhaust pipe gasket damaged Replace.

The muffler loosened Tighten it

The rubber pad cut off Replace.

The exhaust pipe or muffler contacts vehicle body. Correct Abnormal noise

The exhaust pipe or the muffler is damaged. Repair or replace.


88

XV. Parameters for Maintenance

1. List for Technical Parameters of Engine

Technical Parameters list of Engine

Item Standard Value Limits

Camshaft

Camshaft base circle diameter (mm) 36 —

Diameter of camshaft journal (mm) 32.033-32.082 —

Cylinder head and valve

Planeness of cylinder gasket surface (mm) ＜0.03 0.1

Total height of cylinder head (mm) 112.9-113.1 —

Intake valve 1.35 0.85 Thickness of valve edge (mm)

Exhaust valve 1.85 1.35

Diameter of valve stem (mm) Φ5 —

Intake valve 0.020-0.036 0.10 Clearance between valve stem and

valve guide (mm) Exhaust valve 0.030-0.045 0.15

Conical angle of valve 45°-45.5° —

Intake valve 89.61 89.51 Total length of valve (mm)

Exhaust valve 90.91 90.41

Free height of valve spring (mm) 43.1 —

152/33.4 — Load / mounting height of valve spring (N)/(mm)

310/25.2 —

Perpendicularity of valve spring ＜2° 4°

Contact width of valve seat (mm) 0.9-1.3 —

Inner diameter of valve guide (mm) φ5.5 —

Protrusion of valve guide (mm) 23.0 —

Extended by

0.05mm φ10.605-10.615 —

Extended by

0.25mm φ10.805-10.815 —

Diameter of size-extended valve guide on

cylinder head (mm)

Extended by

0.50mm φ11.055-11.065 —

Extended by

0.3mm φ28.425-28.445 —

Intake Extended by

0.6mm φ28.725-28.745 —

Extended by

0.3mm φ26.725-26.745 —

Diameter of size-extended valve seat

ring hole (mm)

Exhaust Extended by

0.6mm φ26.725-26.745 —


89

Item Standard Value Limits

Oil pump and oil pan

Addendum gap of oil pump 0.06-0.18 —

Side clearance of oil pump(mm) 0.04-0.11 —

Clearance of oil pump housing 0.10-0.18 0.35

Piston and connecting rod

Reference outer diameter of piston

(mm)

75.0 —

1st piston ring 0.03-0.07 0.1

Side clearance of piston ring mm) 2nd

piston ring 0.02-0.06 0.1

1st piston ring 0.15-0.30 0.8

2nd

piston ring 0.30-0.50 0.8 Gap of piston ring opening (mm)

Oil ring 0.20-0.50 1.0

Outer diameter of piston pin (mm) 18.0 —

Pressing load on piston pin (under room temperature) (N) 4900-14700 —

Oil gap of crankshaft pin (clearance of connecting rod journal)

(mm)

0.02-0.04 0.1

Side clearance of big end of connecting rod (mm) 0.10-0.25 0.4

Crankshaft and cylinder body

Axial clearance of crankshaft (mm) 0.09-0.27 0.25

Diameter of main journal of crankshaft (mm) 48.0 —

Diameter of connecting rod journal (mm) 42.0 —

Clearance of main journal of crankshaft (mm) 0.02-0.04 0.1

Plainness of surface of cylinder body gasket (mm) <0.03 0.1

Total height of cylinder body (mm) 256 —

Cylindricality of cylinder body (mm) 0.01 —

Reference cylinder bore (mm) 75.0 — —

Clearance between piston and cylinder (mm) 0.02-0.04 —


90

2. Tightening Torques

List of fastener tightening torque

Name Specification Qty. Tightening Torques (Nm)

High strength bolt

Main bearing cap bolt M9×1.25×74.5 8 35±2Nm +60°-64°

(Synchronous fastening machine) 5Nm → 13Nm

+90 ° - 94 ° Connecting rod bolts tightening

torque M6×0.75×33 6

(Manual) 5Nm → 10Nm → 13Nm +45 ° +45 °

alternate tightening

Camshaft bearing cap bolt M6×1×35 12 11±1

Front camshaft bearing cap bolt M8×1.25×30 3 20±1

Cylinder head bolt M9×1.25×143.5 8 24.5±2Nm +180°-184°

Crankshaft pulley bolt M14×1.5×54 1 50Nm±2Nm+60°±2° or 165 Nm±5 Nm

Flywheel bolt M11×1.25×25 6 100±5

Exhaust camshaft sprocket bolt M12×30 1 88±10

E-type bolt

Crankshaft rear oil seal bolt M6×10 E8 6 7.6±0.6

Rear lug blot M8×20 E10 2 18.4±1.4

Intake manifold bolt M8×40 E10 4 18±1.0

Oil pan bolt M6×12 E8 14 7.6±0.6

Sprocket cover bolt I M10×90 E14 2 39.5±3.0

Sprocket cover bolt II M10×50 E14 2 39.5±3.0

Sprocket cover bolt III M6×30 E10 2 8.4±0.6

Bolt M6×20 E10 M6×20 E10 8 8.4±0.6

Bolt M6×12 E10 M6×12 E10 11 8.4±0.6

Bolt M6×45 E10 M6×45 E10 6 8.4±0.6

Bolt M6×25 E10 M6×25 E10 11 8.4±0.6

Bolt M6×12 E8 M6×12 E8 22 8.4±0.6

Cylinder head cover bolt M6×27 E10 10 9±1.0

Oil filter bracket bolt M8×30 E12 3 20±1

Heater water returning pipe bolt M6×20 E8 2 7.6±0.6

Hydraulic oil rail bolt M8×35 E12 2 18.4±1.4

Bolts of exhaust manifold bracket M8×20 E12 2 20±1

Plug

Main oil passage plug I Inner hex M20 2 60±5

Main oil passage plug II Inner hex M12 1 35±5

Water drainage plug Inner hex M12 1 25±5

Oil passage plug Inner hex M10 1 20±2

Oil drainage plug M14×1.5×14 1 39±5


91

Other bolts

Bolts of balance shaft gear M8×15×1.25 1 23.5±4.5

Bolts of balance shaft chain wheel M8×18×1.25 1 45±5

Set track bolts M6×1×12 2 10±2

Dynamic track bolts M8×1.25×15 1 23.5±4.5

Starter bolt M8×55 2 24±3

Oil pressure switch R 1/8 1 10±2

Spark plug M14 3 27.5±2.5

Exhaust manifold stud M8×1×12 6 12±2

Catalytic gas shroud nut M6×1 3 10±1

Q2580614 (crank signal wheel

bolt)

M6 3

12.5±2.5

Water temperature sensor 1 20±4

Hall sensor bolt Inner hex M6×1×16 2 8.4±0.6

Knock sensor bolt Inner hex M8×1.25×30 1 20±4

Exhaust manifold nut M8 5 35±2

Throttle bolts 4 6±0.5

Absolute pressure sensor

self-tapping screw

6±0.5

Square head bolt M10×1.25×90 1 47±5

Idle wheel bolt M10×1.25×38 1 49±9

Oxygen sensor 2 35±5

Oil filter 1

After contact mounting surface, turn by 3 / 4 laps

or 11 ± 1Nm

Bolts of heat shield 1 10±1

Standard parts and threaded connections not mentioned in table above

M6 9-11

M8 20-25

M10 30-50

M12 60-80


92

Section II Engine Lubrication System

I. Precautions

Application Steps of Sealant:

1. Remove any old sealant on the seal gasket by using scraper.

Attention:

Thoroughly remove old sealant from grooves, fixed bolts and bolt holes on sealant application

surface.

2. Wipe sealant surface and matching surface clean with special cleaner, remove water drops, grease

and foreign substances.

3. Set the sealant with specified type completely on appointed position.

1) Install the matching parts in a certain period of time after sealant applied.

2) If there is any dirt on sealant, remove immediately.

3) Do not retighten the bolt and nut after installation.

4) Fill oil and coolant 30min after installation.

Fig. 1.2.001

Scraper


93

II. Preparation

1. Repair Tools

List of repair tools

No. Tool Outline Drawing Explanation

1 Oil pressure gauge

Measure oil pressure

2 Hose

Connect oil pressure

gauge to cylinder

body

3 Oil pressure switch

socket

Dismount and mount

oil pressure switch


94

III. Engine Oil

1. Check

1) Engine oil level

Note: Before starting the engine, park the vehicle steadily to check oil level. If engine has been started,

stop engine and check it after 10min.

① Pull out the oil gauge and clean it .

② Insert the gauge; confirm that the oil level in

engine is between the two marks as shown.

③ Please adjust the oil level if it is out of range.

2) Appearance of engine oil

① Check the engine oil for any white turbidity

and/or severe pollution.

② If the oil is turbid or polluted, it may be caused by engine coolant. Please repair or replace the

damaged parts.

3) Leakage of engine oil

Check the following areas for oil leakage.

Oil pan

Oil drainage bolt on oil pan

Oil pressure switch

Oil filter

Matching surface of cylinder body and cylinder head

Front and rear oil seals of crankshaft

Matching surface of oil pump and cylinder body

4) Inspect oil pressure

Attention:

As the temperature of engine oil is high, please prevent yourself from being hurt.

Check oil pressure after vehicle parked.

Fig. 1.2.002


95

① Check oil level. Please refer to “Engine oil

level”.

② Lift the vehicle, disconnect harness connector

at oil pressure switch and remove the oil

pressure switch.

③ Install oil pressure gauge and hose.

④ Start engine and warm up to normal working temperature.

⑤ Inspect oil pressure when engine operates with no load.

Note: The engine pressure will increase when the temperature of engine oil is low.

If there is obvious difference, please inspect oil circuit and oil pump for leakage.

⑥ Install the pressure switch in accordance with the following steps after inspection:

a. Remove any used sealant attached on pressure switch and engine.

b. Apply sealant as specified and tighten the pressure switch.

Please use the specified sealant: LT5699 or equivalent.


c. After the engine is warmed up, make sure there is no oil leakage during normal operation of engine.

2. Change Oil

Attention:

As the temperature of engine oil is high, please protect yourself from being hurt.

Avoid direct contact of your skin with waste oil for a long time. If contact has taken place, wash

thoroughly with soap or detergent as soon as possible.

① Warmup the engine to check engine compartment for oil leakage. Please refer to “Leakage of

engine oil”.

② Stop the engine and wait for 10min.

Fig. 1.2.004

Fig. 1.2.003


96

③ Loosen engine oil filler cap and remove the oil drain bolt.

④ Discharge the engine oil.

⑤ Install the oil drain bolt with new washer.

Attention:

Be sure to clean oil drain bolt and install with new gasket.

Tightening torque of oil drain bolt: 34-44N·m

⑥ Fill new oil.

Please refer to “Maintenance” for specification and viscosity of oil.

Oil volume: 3.8L

Attention:

Do not pull out oil gauge when filling oil.

The oil filling volume varies with oil temperature and oil drainage time, thus the above data

are only for reference.

Always use oil gauge to check oil filling volume.

⑦ Warm up engine and check the oil drain bolt and oil filter for oil leakage.

⑧ Stop engine and wait for 10min.

⑨ Check the oil level. Please refer to “Engine Oil Level”.

IV. Oil Filter


1) Dismantlement

Dismount the oil filter with an oil filter spanner.

Attention:

Use original oil filter provided by JAC or equivalent.

As the temperatures of engine and engine oil are high, please proetct yourself from being hurt.

During dismantlement, prepare a cleaning cloth to absorb leaked or splashed oil.

Do not make the engine oil stick on drive belt.

Thoroughly wipe and dry the engine oil splashed on the engine and vehicle.

Fig. 1.2.005


97

2) Installation

① Remove any foreign substances attached on

mounting surface of oil filter.

② Apply a film of engine oil on oil seal surface

of new oil filter.

③ Tighten the oil filter until the O-ring seating

on the installation surface; tighten the oil filter

by more 0.75 lap or get the tightening torque

to 11 ± 1N • m.

Attention:

The oil filter must be tightened with filter spanner.

If the filter is tightened by hand, oil leakage may occur due to inadequate tightening torque.


1) Check oil level. Please refer to “Engine Oil”.

2) Start engine to check whether there is oil leakage.

3) Stop engine and wait for 10min.

4) Check oil level and fill as required. Please refer to “Engine Oil”.

Fig. 1.2.006


98

V. Oil Pan and Engine Oil Pump

1. Parts

Breakdown drawing of oil pan and oil pump

1 – Engine oil pump assembly 2 – Automatic tensioner sight hole cover 3 – Front crankshaft oil seal

4 – O-ring 5 – Engine oil collector filter gasket 6 – Engine oil collector filter 7. Oil drainage bolt

washer 8. Oil drainage bolt 9 – Engine oil filter 10 – Oil sump assembly

2. Dismantlement

Caution:

Do not discharge engine oil when engine is hot so as to avoid being hurt.

1) Remove external mounted generator, power steering pump, cylinder head cover and other parts to

the oil pump assembly.

2) Discharge engine oil. Please refer to “Change Engine oil”.


99

3) Dismount oil pan.

a. First, use loosening agent for sealants in order

to prevent oil pan sealing surface from

deformation.

b. Loosen the fixed bolts according to following

sequence: center-both sides.

Tightening torque:7.6±0.6 N·m

c. Knock the special tool into the space between

oil pan and cylinder body as shown in Fig.

1.2.008.

d. Slightly knock the side of special tool, in

order to make the tool move along the sealing

surface of oil pan/cylinder body, and then

dismount the oil pan.

Attention:

Do not damage the matching surface.

4) Dismount oil pump housing assembly.

5) Dismount oil pickup.

Attention:

Tightening torque: 8.4±0.65 N·m

3. Check after Dismantlement

1) Oil pickup

Remove any attached foreign bodies of oil pickup.

2) Oil pump housing assembly

Check the oil hole of oil pump casing assembly for blockage, and clean it if necessary.

Check the oil pump casing assembly for crack or other damage. If there is any, please replace.

3. Installation

1) Install oil filter set.

2) Install pump housing assembly.

3) Install external generator, power steering pump, cylinder head cover and other parts on the oil pump

Fig. 1.2.007

Fig. 1.2.008

Fig. 1.2.009


100

assembly.

4) Install oil filter.

Clean the oil filter mounting surface on oil pump housing.

Apply some oil on O-ring of oil filter.

Tighten oil filter until the O-ring seating on the installation surface; re-tighten the oil filter by 0.75

lap or get the tightening torque to 11 ± 1N • m.

Attention:

The oil filter must be tightened with filter spanner. If the filter is tightened by hand, oil leakage

may occur due to inadequate tightening torque.

5) Install oil pan.

Clean cylinder block and oil pan mating surface to ensure that there are no oil and other impurities.

Apply sealant as shown in diagram below.

Specified sealant: LT5699 or equivalent.

Oil pan

Apply sealant as shown in figure.

Fig. 1.2.010


101

7) Install oil drainage bolt on oil pan

The oil drainage bolt gasket for the oil pan is a

one-time product, new one should be used

after removal.

Install the oil drainage bolt washer of oil pan

shown in the figure.

Attention:

After the installation of oil pan, wait at least

30min before filling engine oil.


1) Check the oil level and fill as required. Please refer to “Engine Oil”.

2) Start engine and make sure there is no oil leakage.

3) Stop engine and wait for 10min.

4) Recheck the oil level. Please refer to “Engine Oil”.

Fig. 1.2.011


102

Section III Cooling System of Engine

I. Cooling Circuit

1. Cooling Circuit Diagram

Cooling circuit diagram

2. Principle Diagram of Cooling

Basic diagram of cooling

Radiator

Expansion tank

Thermostat Thermostat

casing

Water pump

Cylinder body

Cylinder cover

Thermostat off

Thermostat on

Wa

rm a

ir hea

t

exch

an

ge

r

Air th

rottle

bo

dy

Fix

ing b

olts

of coola

nt pum

p p

ulle

y

Coola

nt pum

p p

ulle

r

Bolts for

wate

r pum

p

Wate

r pum

p a

ssem

bly

Seal ring o

f w

ate

r pum

p

Heate

r w

ate

r re

turn

ing p

ipe b

olts I

Heater water returning pipe bolts II

Heater water returning pipe

Spacer of heater water returning pipe

Thermost subassembly

Water pump feeder

Water pump inlet bolt

Thro

ttle

pre

-heating o

utlet hose

Thro

ttle

pre

-heating o

utlet hose


103

II. Engine Coolant

1. Check

1) Level check

After the engine cooled, check whether coolant level in reservoir is between MIN and Max marks.

Adjust level if necessary.

2) Leakage check

Apply pressure to cooling system with leak

detector of radiator cap to detect any leakage.

3) Test pressure

Caution:

Please do not dismount radiator cap when engine is very hot, otherwise the high-pressure engine

coolant overflowing from radiator will cause severe burns.

Attention:

Test pressure over specified value may cause radiator damaged.

When it is detected that the engine coolant is insufficient, fill engine coolant into radiator. If any

parts are damaged, please repair or replace.

2. Change Coolant

Caution:

To avoid being burned, please do not change coolant when engine is hot.

Wrap up the radiator cap with thick cloth, and turn to open it carefully. Release the pressure in

radiator first, and then fully remove cap.

Fig. 1.3.001

Fig. 1.3.002


104

Be careful not to splash engine coolant onto the drive belt.

1) Discharge engine coolant

① Dismount the deflector on right side of engine.

② Open the water drain plug at the bottom of radiator, and then open the radiator cover.

③ If necessary, remove coolant reservoir to discharge coolant and clean the reservoir before

reinstallation.

④ Check the discharged engine coolant for rust or other impurities or discoloration.

If it is polluted, please wash the engine cooling system. Refer to “Wash Cooling System”.

2) Refill coolant

① Install removed coolant reservoir and water drain plug of radiator.

Attention:

Be sure to clean the water drain plug and install with new O-ring.

② Make sure all the hose clamps have been tightened firmly.

③ Dismount the air filter upper cover and air intake hose. Please refer to “Air Filter Assembly”.

④ Disconect the outlet pipe of warm water pipe. Please lift the hose as high as possible.

⑤ Fill coolant into radiator and reservior until specified level is achieved. The coolant should be filled

slowly allowing air in system can be bleed gradually.

Attention:

The original engine coolant provided by JAC must be used. Please refer to “Recommended Oil

and Lubricant”.

Disconnect when engine coolant overflows from warm water pipe, and then reconnect and

continue to fill engine coolant.

⑥ Install air filter upper cover and air intake hose. Please refer to “Air Filter Assembly”.

⑦ Install radiator cap.

⑧ Warm up engine until the thermostat is turned on.

Touch the lower water pipe of radiator to detect whether there is any warm water flows out, so as to

verify that the thermostat has been turned on.

Attention:

Check the engine water temperature indicator to avoid overheating of engine.

⑨ Stop engine to lower the engine temperature.

Cooling time can be reduced by using fan.

Fill coolant in radiator through the filler if necessary.


105

⑩ Fill engine coolant in reservoir to the MAX position.

⑪ Install the radiator cap and repeat steps ③- more than twice until ⑨ the engine coolant level does

not lower any more.

⑫ Run the engine to check the cooling system for leakage.

3) Wash cooling system

① Install the dismounted radiator water drainage plug and reservoir.

Attention:

Be sure to clean the water drainage plug and mount the new O-ring.

② Dismount air filter upper cover and air intake hose. Please refer to “Air Filter Assembly”.

③ Remove outlet pipe of warm water pipe. Please lift the hose as high as possible.

④ Fill engine coolant into radiator and coolant reservoir, and install radiator cap.

Remove connection when engine coolant overflows from warm water pipe, and then reconnect and

continue to fill engine coolant.

⑤ Install the air filter upper cover and air intake hose. Please refer to “Air Filter Assembly”.

⑥ Run engine to warm it up to normal working temperature.

⑦ Increase engine speed for several times with no load applied to the engine.

⑧ Stop engine and wait for it to cool.

⑨ Discharge the water in system. Please refer to “Discharge engine coolant”.

⑩ Repeat steps ①- until the radiator begins to discharge the cleared water.⑨

III. Radiator


Caution:

Please do not dismount radiator cover when engine is very hot, otherwise the high-pressure

engine coolant will cause severe burns. Wrap up the radiator cover with thick cloth and slowly

turn it to discharge the air pressure inside. Turn and open the radiator cover and take it off

carefully after the pressure is fully released.

1) Dismantlement

① Dismount engine deflector. Please refer to “Deflector”.

② Discharge engine coolant in radiator. Please refer to “Replace Engine Coolant”.

Attention:

Operate after engine is cooled.

Please do not make the engine coolant splash onto the drive belt.

③ Dismount air intake pipe and take it off.

④ Disconnect the harness connector of radiator fan motor and move it aside.


106

⑤ Dismount the inlet and outlet hoses of radiator and returning hose of coolant reservoir.

⑥ Dismount bracket of radiator and take off the radiator and fan subassembly.

Attention:

Please do not damage or scratch the radiator core during dismantlement.

⑦ Disassemble cooling fan sub-assembly from radiator.

2) Installation

Install in the reverse order with dismantlement.

3) Check after Installation

Check if there is any engine coolant leakage with leak detector for radiator cover. Please refer to

“Leakage Check”.

Start and warm up the engine. Visually inspect whether there is any coolant leakage.

2. Inspect Radiator Cap

1) Pull out the negative pressure valve and open it. Check if it can be fully closed after pressure

release.

Make sure there is no dirt on or damage to negative pressure valve seat of radiator cover.

Make sure the opening and closing operations

of negative pressure valve are normal.

2) Inspect relief pressure of radiator cap.

Standard value: 78-98KPa

Limit: 59KPa

Connect the radiator cap to the leak detector for

radiator and apply engine coolant to sealing face

of the cover.

Replace radiator cap if operation of negative

pressure valve is abnormal or the relief pressure

decreases below limit.

3. Inspect Radiator

Check the radiator for slurry or blockage. If necessary, wash the radiator surface with following

methods.

Be careful not to bend or damage the radiating fin.

Fig. 1.3.003

Fig. 1.3.004


107

When washing the radiator without dismantling it, please dismount all accessories such as cooling

fan, wind collection cover and horn. Then wrap up the harness connectors with adhesive tape to

prevent water from flowing in.

1) Wash back of radiator core from top to bottom with the water hose pointing to the radiator

vertically.

2) Wash each surface of radiator core every 1min.

3) If no dirt is washed off radiator, washing must be stopped.

4) Vertically blow the back radiator downwards with compressed air. Apply the compressed air with

pressure lower than 490KPa and keep the distance above 30cm.

5) Blow each surface of radiator core with compressed air every 1min until no water is blown out.

IV. Radiator Cooling Fan


1) Dismantlement

① Dismount the air intake pipe and take it off.

② Disconnect the harness connector of radiator fan motor and move it aside.

③ Dismount the radiator cooling fan sub-assembly.

Attention:

Do not damage or scratch radiator core during dismantlement.

2) Installation



1) Disassembly

① Dismount the cooling fan from fan motor.

② Dismount the fan motor from wind collection cover.

2) Check after disassembly

① Cooling fan

Check the cooling fan for cracks or abnormal bend. If any, replace the cooling fan.

② Fan motor

Check the motor for sticking.

3) Assembly

Assemble in the reverse order with disassembly.

V. Water Pump


108


Attention:

Be careful not to splash the engine coolant onto the drive belt while dismantling the water pump.

If the water pump can not be disassembled, it should be replaced as a whole.

After the installation of water pump, connect the hose, fix it with clamping band, and then check

if there is any leakage with leak detector for radiator cover.

1) Dismantlement

① Discharge the engine coolant in radiator.

Please refer to “Replace Engine Coolant”.

② Loosen the fixed bolt for belt pulley of water

pump.

③ Dismount the drive belt. Please refer to

“Drive Belt”.

④ Dismount the fixed bolt for water pump.

Attention:

Tightening torque: 8.4±0.65N·m


Check the water pump body assembly for severe corrosion, leakage of water-seal and erosion.

Check the water pump bearing for jamming or other damages. Replace the bearing if necessary.

3) Installation

① Clean water pump installation seat.

② Installation of pumps and replacement of the pump seals.

Attention:

Do not let the seal ring drop during installation.

Alternately and evenly tighten fixing bolts of water pump.

Fig. 1.3.005

Fig. 1.3.006


109

a）. Install belt pulley of water pump.

b）. Install drive belt and adjust it in accordance with specified tension. Please refer to “Drive Belt”.

c）. Fill engine coolant. Please refer to “Refill engine coolant”.


Check if there is any coolant leakage with leak detector for radiator cap. Please refer to “Leakage

Check”.

Start and warm up the engine. Visually inspect if there is any engine coolant leakage.

VI. Thermostat Sub-assembly


1) Dismantlement

① Discharge the engine coolant through water drain

plug of radiator. See “Replace Engine Coolant”.

Attention:

Operate after the engine has cooled.

Please do not splash the engine coolant onto

the drive belt.

② Disassemble water inlet pipe and heater returning

pipe of radiator at thermostat side.

③ Disconnect the harness connectors of coolant

temperature sensor and water temperature alarm

switch and fixed bolts for support racks of harness

connectors of front and rear oxygen sensors, and

then remove them.

④ Unscrew water pump inlet bolt, remove the

thermostat.

Fig. 1.3.008

Fig. 1.3.009

Fig. 1.3.007


110


① Thermostat

Inspect opening of thermostat valve at normal

room temperature.

Temperature of thermostat (ON): 82 (initially open)

95 (fully open)

Maximum lift of valve stem: ≥8mm

Please replace the thermostat when the measurement exceeds the specified range.

② Water pump inlet and thermostat housing

Check them for cracks and other damages.

3) Installation


① Be careful not to splash engine coolant onto the engine and wipe and dry the engine coolant with

cleaning cloth.

② Replace the thermostat seal ring.

Attention:

Do not apply engine oil or other oil substances to the seal ring.

Water pipes on thermostat housing must be installed solidly.

③ When mounting thermostat, its poppet valve

must be set at the highest position.

④ If the water temperature alarm switch needs

to be reused, apply specified sealant to its

thread.


Fig. 1.3.010

Fig. 1.3.011

Fig. 1.3.012

Highest


111

⑤ If the engine coolant temperature sensor

needs to be reused, apply specified sealant to

its thread.



Check for any coolant leakage with leak

detector of radiator cap. Please refer to


Start and warm up the engine. Visually inspect if there is any engine coolant leakage.

VII. Water Piping Sub-assembly

1. Dismantlement

① Discharge the engine coolant through water drainage plug at the bottom of radiator. Please refer to

“Replace Engine Coolant”.

Attention:

Operate after the engine has cooled.

② Dismount the air filter assembly. Please refer to “Air Filter Assembly”.

③ Dismount the upper and lower water hoses of radiator.

④ Dismount the warm water hose and minor cycle water piping.

⑤ Unscrew water inlet pipe bolt before disassembling the water inlet pipe from back of water pump.

Attention:

Please dismount the negative terminal of battery before dismantlement.

2. Installation

Be aware of following precautions and install with steps contrary to dismantlement.

1) Firmly insert each hose. Mount the clamp properly so that it will not clamp the raised position of

water piping.

2) Replace the steel water returning pipe gasket of heater.

Attention:

Do not apply engine oil or other oil substances to the seal ring.

Water pipes on thermostat housing must be installed solidly.


1) Check if there is any engine coolant leakage with leak detector for radiator cap. Please refer to


2) Start and warm up the engine. Visually inspect if there is any engine coolant.

Fig. 1.3.013


112

VIII. Trouble Analysis

Table for Overheating Cause Analysis

Symptom Item should be inspected

Water pump malfunction Worn or loosening of drive

belt

Stuck of thermostat at

closed position

Blockage due to dust or

paper scraps Radiator is damaged

Mechanical damage

Improper heat radiation

The radiator cooling is

blocked

Excessive foreign

substances (corrosion,

pollutants, sand, etc.)

—

The cooling fan fails to

work

The resistance for fan

rotation is too large Insufficient air flow

The fan blade is

damaged

Fan assembly —

Damaged wind collection

cover — — —

Incorrect blend ratio of

coolant — — —

Poor quality of engine

coolant — Viscous engine coolant

Loose clamp Coolant hose

Broken hose

Water pump Improper sealing

Looseness

Poor sealing

Broken radiator coolant

reservoir Radiator cap

Broken radiator core

Failed

Parts o

f Coo

ling

Sy

stem

Insufficient engine coolant Engine coolant leaks

Coolant reservoir Breakage of stock solution

tank

Excessively high engine

speed in the case of no-load

Long-term traveling

— The engine is overloaded Abnormal driving

Driving at ultra high-speed

Drive train failure

Wheel and tyre with

incorrect specifications

mounted

Braking drag

Incorrect ignition timing

—

The vent of bumper is

blocked —

Cover mounted The radiator grill is

blocked Blockage of slurry or paper

scraps

The radiator is blocked —

Tro

ub

le of P

arts of O

ther S

ystem

s

Poor ventilation

The condenser is

blocked Poor ventilation

—


113

IX. Parameters for Maintenance

Technical specification for cooling system

Temperature of thermostat opening 82 (Initiall y open) 95 (Fully open)

Maximum lift of thermostat valve stem >8mm


114

Section IV Fuel Supply System of Engine

I. General Precautions

Caution:

The following rules should be complied with during the replacement of parts of fuel pipeline.

Set the mark “Attention: combustive” in workshop.

Be sure to operate in the well-ventilated area, and prepare C02 fire extinguisher in the operation

workshop.

Do not smoke during the fuel system servicing. No fire in working area.

Hold the discharged fuel in the container and cover it. Put the container in safe area.

When disassembling the fuel pipe components, note the following:

Disconnect negative pole of battery.

Replace with new clips all the time.

Do not distort the fuel pipe during installation.

Please operate on level ground.

Connect the fuel pipe joint and make sure the joint has been fixed. Make sure the joint and resin

pipe don’t contact any adjacent parts.

Do not excessively tighten the hose clips to prevent damage of hose.

Check each connection for fuel leakage according to following steps after installation of fuel pipe.

- Set the ignition switch at “ON” position to apply fuel pressure on fuel pipeline (do not start the

engine). Then check each connection for fuel leakage.

- Start the engine, increase its speed and check each connection for fuel leakage.

Only the original fuel filler cap provided by JAC can be used.

Please refer to “Fuel Evaporative Emission System” for maintenance of parts of the system.


115

II. Preparation

The special tools are listed in the table below:

List of Special Tools

S.N. Tool Outline Diagram No. Explanation

1 Fuel pressure

gauge

JAC－T1F018 Measure fuel pressure

III. Fuel System

1. Check Fuel Pipe

Check the fuel pipeline, fuel filler cap and fuel tank for proper installation, leakage, crack, damage,

loose connection, worn and aging.

2. Inspect Fuel Pressure

Attention:

Always keep the joints of fuel hose sealed with O-ring.

Do not operate electrical system during inspection.

Prepare a container under the fuel pipe to be disconnect to avoid fuel splash.

1) Fully release fuel pressure. Please refer to “Release Fuel Pressure”.

2) Dismount the nut for fuel pressure inspection door on fuel injector guide rail.

3) Connect fuel pressure gauge.

4) Set ignition switch at “ON” position and check for fuel leakage.

5) Start engine and check if there is fuel leakage.

6) Obtain the reading shown in fuel pressure gauge.

Fuel pressure: 350KPa

Attention:

Do not check fuel pressure during system operation.

During the Inspection of fuel pressure, please always check the fuel piping for leakage.

7) If the check result is not good, turn to the next step.


116

8) Check for the following matters.

- Blockage of fuel hose and fuel pipe.

- Blockage of fuel filter.

- Fuel pump and its control circuit.

IV. Fuel Injector and Guide Rail

1. Dismantlement

Caution:

Do read the “General Precautions” before dealing with fuel system. Please refer to “General

Precautions”.

1) Disconnect the PCV hose joint at intake

manifold side.

2) Disconnect the injector wiring harness

connector

3) Disconnect the joint of fuel hose on fuel

guide rail.

Fig. 1.4.001

Fig. 1.4.002

Fig. 1.4.003


117

Attention:

Please prepare the container and cleaning cloth in advance as fuel leakage may take place.

Avoid the naked flame and spark.

Please keep any parts away from heat source. Special attention must be paid when welding

around them.

Do not expose the parts to the electrolyte of battery or other fluid.

Keep the connection clean and prevent damage and foreign substance, and properly cover the

connection with plastic bag or equivalent.

4) Dismount the fixing bolt for fuel guide rail.

5) Take off the fuel guide rail with injector from intake manifold.

Attention:

Avoid interference with fuel injector during removal.

Absorb the fuel leaked from fuel pipe with cleaning cloth.

6) Dismount the fuel injector from fuel guide rail with following steps:

a. Pry and dismount the snap-in.

b. Straightly pull out the fuel injector from fuel pipe.

Attention:

Pay attention to the leakage of residual fuel in fuel pipe.

Do not damage the nozzle of fuel injector.

Do not make it fall off or knock it.

Do not disassemble it.


1) Fuel Injector

Check the upper and lower seal rings of fuel injector for crack, aging and breakage. If any, please

replace.

Fig. 1.4.004


118

Check the injection hole of fuel injector for blockage. If any, please wash or replace by using

special instrument.

2) Fuel Guide Rail

Check the fuel inspection hole for damage and jamming. If any, please replace.

Check if there is residuum in guide rail. If any, please clean.

3. Installation

1) Be aware of following precautions when mounting new O-ring on fuel injector.

As the upper and lower O-rings are different, do not confound them.

Fuel pipe side: thick one

Nozzle side: thin one

Please mount the O-ring by your hands.

Lubricate the O-ring with petrol.

Do not wash O-ring with solvent.

Verify that there is no foreign substance on O-ring and its matching part.

Make sure the O-ring will not be scraped by tool or fingernail, and it is not distorted or stretched

during installation.

Insert new O-ring into fuel injector straightly.

Do not deflect or distort it.

2) Mount fuel injector ④ on fuel pipe ①with

following steps.

③ : thick one

⑤ : thin one

a. Insert the snap into the fixing groove on ②

fuel injector. Insert the snap slice D into

raised position F of fuel injector.

Attention:

Replace with the new snap every time.

Make sure there is no interference between the snap and O-ring.

b. Insert fuel injector into fuel pipe where snap has been mounted.

Attention:

Make sure the direction of insertion aligns with the axis.

Fig. 1.4.005


119

Insert the snap slice C into the raised position B of fuel pipe.

Make sure the flange A of fuel pipe is properly mounted in the fixing groove on snap flange.

c. Make sure the fuel injector will not move or fall off. Installation is completed.

3) Install fuel pipe guide rail and fuel injector assembly inside intake manifold.

Attention:

Be careful not to make fuel injector nozzle contact with other parts.

4) For the following steps, install with steps contrary to dismantlement.


Check for fuel leakage with following steps.

1) Set the ignition switch at “ON” position (when the engine stops), and then check the connection of

fuel pipe for leakage.

2) Start the engine, increase its speed and recheck the connection of fuel pipe for leakage.

V. Fuel Filter

1. Dismantlement

Caution:

Do read the “General Precautions” before dealing with fuel system. Please refer to “General

Precautions”.

Attention:

The fuel filter should be periodically replaced in accordance with the maintenance instruction

specified in “User’s Manual”.

1) Open the fuel filler cap.

2) Release the pressure in fuel tank.

3) Dismount the rear seat cushion. Please refer

to “Rear Seat”.

4) Dismount the service lid for fuel tank.

Directly prize it up with flat end screwdriver.

Fig. 1.4.006


120

5) Disconnect the fuel pipe joint 1 (at fuel pump

side), joint 2 (at fuel filter side) and

grounding end 3 of fuel filter.

Attention:

The fuel filter should be wrapped up with towel

or equivalent, so as to avoid injection of

residual fuel.

Disconnect joint with following methods:

Hold the side edge of joint and press the

raised position of joint to pull out the fuel

pipe.

If the joint attaches to the resin pipe, push and

pull the joint for several times until it moves,

and then pull out the joint.

Attention:

The joint can not be disconnected when the

raised position is fully pressed down. Do not

excessively distort the joint.

Do not disconnect the joint with any tool.

Prevent the resin pipe from being heated. Special attention must be paid when welding around

the resin pipe.

Prevent the resin pipe from contacting acidic fluid such as electrolyte of battery.

Do not bend or distort the resin pipe during installation and dismantlement.

To keep the connection clean and prevent from damage and foreign substance, please fully cover

them with plastic bag or equivalent.

6) Take off the fuel filter and fuel pipe.

2. Installation


3

2

Fig. 1.4.008

1

Fig. 1.4.007

Fig. 1.4.009


121

1) Fuel filter

Be aware of correct installation direction of

fuel filter.

towards fuel inlet pipe side

2) Connector

Connect the connector of fuel supply hose according to following methods:

① Check the connection for foreign substance or damage.

② Make the connector align with the resin pipe and insert the connector straightly until “click” is

heard.

③ Check whether the connector is connected properly with following methods after connection.

Visually inspect that 2 raised positions have been connected to the connectors.

Stretch the resin pipe and its connector hard

to verify that they have been firmly

connected.


Check whether there is fuel leakage with following steps.

1) Set ignition switch at “ON” position (when engine stopped), and then check the connection of fuel

pipe for leakage.

2) Start engine, increase its speed and recheck the connection of fuel pipe for leakage.

Fig. 1.4.010

Fig. 1.4.011


122

VI. Fuel Pump Assembly

Figure of fuel pump assembly

1. Dismantlement

Caution:

Do read the “General Precautions” before dealing with fuel system. See “General

Precautions”.

1) Check fuel level indicated on fuel meter. If the meter indicates “full” or “to be full”, discharge the

fuel from tank until the meter indicates that the fuel level is lower than position “E”.

Attention:

If fuel level exceeds mounting surface of fuel level sensor, the fuel may overflow during the

dismantlement of fuel level sensor.

2) Open the fuel filler cap.

3) Release the pressure in fuel tank.

4) Dismount the rear seat cushion. Please refer to

“Rear Seat”.

5) Dismount the service lid for fuel tank.

Directly prize it up with flat end screwdriver.

Fig. 1.4.012


123

6) Disconnect the harness connector of fuel

pump and fuel pipe joint.

① Fuel pipe joint of fuel pump

② Harness connector of fuel harness

Disconnect the joint with following methods:

Hold the side edge of joint and press the raised position of joint to pull out the pipe.

If the joint sticks on the resin pipe, push and pull the joint for several times until it moves, and then

pull out the joint.

Attention:

The joint can not be disconnected until the raised position is fully pressed down. Do not

excessively distort the joint.

Do not disconnect the joint with any tool.

Prevent the resin pipe from being heated. Special attention must be paid when welding around

the resin pipe.

Prevent the resin pipe from contacting with acidic fluid such as electrolyte of battery.

Do not bend or distort the resin pipe during installation and dismantlement.

To keep the connection clean and prevent damage and foreign substance, please fully cover them

with plastic bag or equivalent.

7) Loose and take off the locknut with special

tool.


Fig. 1.4.014

1 2

Fig. 1.4.013


124

8) Take off the Y-ring.

Attention:

Tilt the fuel pump when it is taken out, so

as to avoid broken of fuel level sensor.

To avoid residual fuel from being polluted,

wrap the Y-ring with cloth to pull it out

straightly.

9) Take off the fuel pump.


1) Fuel pump

① Visual Inspection

Check for broken or fuel impurity. If any, please replace or wash it.

② Inspect Fuel Pump Operation

Actuate the fuel pump with 12V regulated power supply directly and check if the operation is

normal.

Attention:

Do not make the fuel pump operation for a long time, so as to avoid damage of pump plunger.

2) Y-ring

Check it for material loss and broken.

3) Locknut

Check for deformation, crack, material loss, broken, and damage at mounting thread.

4) Fuel Level Sensor

Check the fuel float for interference and oxidation of its surface.

3. Installation


1) Fuel pump assembly

Fig. 1.4.016

Fig. 1.4.015


125

The Y-ring must fully fit with fuel tank during installation.

Tilt the fuel pump to facilitate its installation and pay attention to its direction.

There should be no turn-up on Y-ring during the installation.

Pre-tighten the locknut during its installation, and then tighten it horizontally.

2) Connector

Insert the connector of fuel supply hose with following methods:

① Check the connection for any foreign substance and damage.

② Make the connector align with the resin pipe and insert the connector straightly until “click” is

heard.

③ Check whether the connector is properly connected with following methods after connected.

Visually check whether the 2 raised positions have been connected to the connectors.

Stretch the resin pipe and its connector hard and make sure they have been firmly connected.


Check for fuel leakage with following steps.

1) Set ignition switch at “ON” position (when engine stops), and then check the connection of fuel

pipe for leakage.

2) Start the engine, increase its speed and recheck the connection of fuel pipe for leakage.


126

VII. Fuel Tank Assembly

Breakdown diagram of fuel tank assembly

1-Filler cap 2-Filler tube 3-Fuel tank 4-Fastening band of fuel tank 5-Service lid 6-Locknut

7-Y-ring 8-Fuel pump 9-Fuel filter 10-Thermal baffle


1） Dismantlement

Caution:

Do read the “General Precautions” before dealing with fuel system. See “General Precautions”.

Discharge fuel tank if necessary. Please refer to “Fuel Pump”.

Please operate on level ground.

① Carry out the dismantlement steps 1-6 of fuel pump. Please refer to “Fuel Pump”.

② Disconnect fuel supply hose and vent hose.

③ Disconnect EVAP hose.

④ Support the fuel tank with special jack.

Attention:

The fastening band of fuel tank should not be blocked in supporting position.

⑤ Dismount the clamping bands of filler tube and fuel tank, and then disconnect the filler tube and

fuel tank.

⑥ Dismount fastening band of fuel tank.


127


⑦ Manually support the tank and carefully

lower the jack to dismount fuel tank.

Attention:

Make sure all connections have been

disconnected.

Make sure there is no interference with

vehicle.

2) Check after dismantlement

① Fuel tank

Check for impurity of fuel. If any, clean it with hot water.

Capacity of fuel tank: 45L

② EVAP hose and clips

Check the hose for blockage, corrugation, deformation and breakage.

Check the clips for damage or breakage.

③ Reinforced plate and its backing plate

Check the surface of reinforced plate for scratch and deformation.

Check the backing plate for crack, material loss, deformation and breakage.

3) Installation


Firmly hold fuel supply hose to insert it.

Do not set the hose clamp in expansion area of fuel pipe.

Please refer to “Fuel Pipe Joint” for precautions of fuel pipe joint connection.


Check for leakage with following steps.

① Set ignition switch at “ON” position (when engine stops), and then check the connection of fuel

pipeline for leakage.

② Start the engine, increase its speed and recheck the connection between piping and fuel pipe of fuel

system for leakage.

Fig. 1.4.017


128

Section V Emission Control System of Engine

I. Fuel Evaporation Control System

1. Description

Schematic diagram of fuel evaporation system

The fuel evaporation system is used to reduce hydrocarbon compositions emitted into ambient air from

fuel system. Reduction of hydrocarbon is achieved by using active carbon in EVAP carbon canister.

When the engine is stopped or fuel is filled, the fuel evaporation from sealed fuel tank will be

introduced into EVAP carbon canister with active carbon and stored there. During operation of engine,

the fuel evaporation in EVAP carbon canister will be introduced into intake manifold through clean

passage. EVAP carbon canister is controlled by ECM. With engine running, evaporation flow controlled

by EVAP canister solenoid is adjusted with direct proportion of increased air flow. During deceleration

and idling, the evaporation passage may be cut off by EVAP carbon canister solenoid.

Air cleaner

Intake manifold

EVAP carbon canister

solenoid valve

Fuel tank

EVAP carbon

canister

Fuel evaporation

Air


129

2. Diagram of Fuel Evaporative Emission Pipeline

Diagram of fuel evaporative emission pipeline

1-Carbon canister assembly 2-Fuel inlet hose of engine 3-Pipe connecting carbon canister with solenoid valve

4-Hose connecting carbon canister with solenoid valve 5-Fuel inlet pipe of engine 6-Fuel filter

Note:

Do not use soap water or any other detergent when

installing vacuum pipe or cleaning pipeline.

3. Inspection of parts

1) EVAP carbon canister

① Check EVAP carbon canister with following

methods:

a. Plug port 1, blow at port 3, make sure the air

flows out from port 2 freely.

b. Plug port 3, blow at port 1, make sure the air

flows out from port 2 freely.

② Dismount the vacuum hose

Loose the clamps between carbon canister and fuel tank and carbon canister solenoid valve with

slip-joint pliers, pull out the vacuum hose.

1 2

3

Fig. 1.5.001

1

2

3

4

5

6


130

③ Dismount the carbon canister

Lift the carbon canister and dismount it from the

bracket on inner lining of left fender.

2) EVAP carbon canister solenoid valve

The air flow rate is controlled by the opening of evaporation by-pass passage in EVAP carbon canister

solenoid valve. The solenoid valve will repeat the operations of “ON” and “OFF” with signal from ECM

to actuate the variation of valve opening, so as to optimize engine control. The optimum value

memorized in ECM lies on the state of engine. When the engine operates, flow rate of fuel evaporation

from EVAP carbon canister is adjusted along with the variation of air flow.

① Instruction of parts

Flow rate of fuel evaporation from EVAP carbon canister is controlled by duty cycle of ON/OFF of the

solenoid valve. The solenoid valve is actuated by ON/OFF duty cycle signal from ECM. The wider the

pulse width in “ON” condition is, the more fuel evaporation will flow through the valve.

② Dismantlement

a. Disconnect the vacuum hose of EVAP carbon

canister solenoid valve.

左前车架左前车架左前车架左前车架

Fig. 1.5.003

Fig. 1.5.002 Left front frame


131

b. Disconnect the harness connector of EVAP

carbon canister solenoid valve.

c. Remove the EVAP carbon canister

electromagnetic valve.

3) Filler cap

Vacuum relief valve is mounted at the filler cap. When the pressure in fuel tank is high (more fuel

evaporation), the vacuum relief will be closed, so as to avoid emission of fuel evaporation to ambient air.

When the pressure in fuel tank is low (negative pressure), the vacuum relief valve will be opened, so as

to enable the outside air to get into fuel tank.

Fig. 1.5.004

Fig. 1.5.005


132

II. Forced Ventilating System of Crankcase

1. System Illustration

The forced ventilating system of crankcase is used to bring the cylinder blow-by gas in crankcase back

to intake manifold.

It is the forced ventilating valve (PCV) which brings the cylinder blow-by gas in crankcase back to

intake manifold. With throttle partially opening, the intake manifold sucks blow-by gas of crankcase

through PCV valve. In normal conditions, the ventilation volume of PCV valve is sufficient to suck all

blow-by gas of crankcase and a little air. The vent air is brought into crankshaft through air intake pipe.

Ventilation hose inhales fresh air from the rear end of the air filter to the crankcase to keep the crankcase

pressure at a certain range. When the air throttle is fully open, the vacuum degree is not sufficient to

open PCV valve and thus unable to suck blow-by gas of crankcase. The air flows through connecting

hose in reversed direction. In vehicles with severe blow-by gas, PCV valve can not meet the

requirements because part of air may get into the air intake pipe at any time during operation.


133

2. Inspection of Element

Check the PCV (forced ventilation of crankcase) valve as shown below:

1) Operation principle

Operation principle list of PAV valve

Valve chamber cover side


Operating state of engine Out of work Operating state of engine Idling or deceleration

PCV valve Out of work PCV valve Fully open

Variation of vacuum Limited Variation of vacuum Slight



Operating state of engine Normal operation Operating state of engine Improper acceleration and

high speed

PCV valve Normal operation PCV valve Retardant operation

Variation of vacuum Large Variation of vacuum Extremely large

No vacuum High vacuum

Moderate No


134

2) Dismantlement and Installation

① Dismantlement

a. Disconnect the PCV valve hose from cylinder

cover.

b. Remove the PCV valve from cylinder

cover.


① PCV valve: Hissing may be produced during

normal working of valve with air flows

through. When finger touches the valve at the

entrance, you can immediately feel a strong

vacuum pressure.

② Vent hose of PCV valve

a. Check the hose and joint for leakage.

b. Disconnect all hoses and clean with compressed air. If the blockage in hose can not be cleared,

replace.

Fig. 1.5.006

Fig. 1.5.007

Fig. 1.5.008

P.C.V valve

Maintenance Manual for J2 Sedan Electrical Part of Engine

135

Chapter II Electrical Part of Engine

Section I Ignition System

I. Ignition coil

1. Parts

Ignition coil

2. Dismantlement & Installation

1) Dismantlement

Attention:

Be sure that the ignition switch is in the

“OFF” position.

① Dismount the trimming cover of engine.

Refer to “Intake Manifold” section.

② Disconnect the wiring harness connectors of

the ignition coil from high voltage ignition

coil.

Fig. 3.1.001


136

③ Remove high-voltage ignition coil bolt to

remove coil.


④ Dismount the spark plug with special socket.


Attention:

Please do not drop or shake it.


① High-voltage ignition coil

Check the primary coil resistance between both terminals.

Primary coil resistance: 0.77-0.95 Ω

Check the resistance of secondary coil

Secondary coil resistance: 7.75-10.23 KΩ

Attention:

The ignition coil harness connector must be disconnected for secondary coil resistance

measurement.

② Spark plug

Check the spark plug:

Check insulator of spark plug for damage and broken.

Check spark plug for carbon deposit. See the following table for causes of carbon deposit.

Causes of Carbon Deposit

Phenomenon Black charcoal Hard charcoal

Reason Impurity in the fuel or high fuel-air

ratio.

Impurities in the fuel; wrong

ignition timing, or untight spark

plug.

Check spark plug electrodes for damage.

Inspect clearance of spark plug.

Fig. 3.1.002


137

Inspect clearance of spark plug by using feeler.

Standard value: 0.7-0.8 mm

If the clearance is beyond the standard value, replace.

Check sparking ability of spark plug.

a. Connect spark plug to high voltage circuit.

b. Keep the distance between edge of spark plug and the grounding metal at about 14 mm.

c. Start the engine for about 3s, check whether there are sparks produced between the edge of spark

plug and the grounding metal.

Attention:

During check, be careful not to get an electric shock.

If the clearance is less than 14 mm, the sparks may also be produced even though the high

voltage wire has trouble.

If there are no sparks, replace spark plug.

3) Installation


II. Diagnosis of Common Troubles

Diagnosis Common Troubles

Symptom Possible causes Solution

Trouble of ignition coil or ignition

switch

Check or replace the ignition coil or the

ignition switch

Trouble of spark plug Check or replace spark plug

The engine can’t or is

difficult to start.

Disconnected high voltage wire Check the high voltage wire

Trouble of high voltage wire or spark

plug

Check the high voltage wire or check or

Replace spark plug

Unstable idle speed

Trouble of ignition coil Check or replace the ignition coil

Trouble of high voltage wire. Check the high voltage wire Engine surge or poor

acceleration Trouble of spark plug Check or replace spark plug

Poor. fuel economy Trouble of spark plug Check or replace spark plug

III. Parameters for Maintenance

Maintenance Specification of Ignition System

Primary coil resistance 0.77-0.95Ω High voltage

Ignition coil Secondary coil resistance 8.7±0.87 KΩ

Spark plug Spark plug clearance 0.7-0.8mm


138

Section II Starting and Charging System

I. Principle Diagram of Starting and Charging System

ENG电动机

单向离合器

电磁开关

蓄电池

熔断片

起动机

充电指示灯+-

发电机

整流器

磁场绕组 DfR1 R3

R2

R4

ZD

Tr2

Tr1定子绕组

点火开关

组合仪表

熔断片120A30A

中央电器盒

LOCKACCACC ON O/S

START

防盗继电器

ETACS-低电平有效

起动继电器

接地

熔断片20A

B LS

E

Principle Diagram of Starting and Charging System

II. Battery

1. How to use battery

Attention:

If the engine is necessary to be started with auxiliary battery and jumper wire, 12 V auxiliary

battery should be used.

When jumper wires are connected with battery, make sure that the jumper wires are clamped

to the terminals of battery and have good contact.

2. Methods to prevent excessive discharging of battery

The following precautions should be particularly emphasized to prevent excessive discharging of

battery.

Always keep surface of battery (esp. the top) clean and dry.

The connecting part of the terminals should be clean and tightened.

ETACS－low level effective

Anti-theft relay

Ignition switch

Central electric box

Electric

generator

30 A fuse link

Batte

ry

120 A fuse link

Combined

device

Magnetic field

winding

Stator winding

Starter

Rectifier

Solenoid

switch

Charging alarm light

One-way clutch

Electric

motor

20 A fuse link

Starting relay

Grounding


139

If the vehicle is not used for a long time, the cathode terminal of battery should be disconnected.

Check charging condition of battery.

3. Check

1) Visual inspect

Check terminals of battery for damage and electrolyte leakage. If any, replace.

2) Voltage inspection: Inspect batter for proper voltage. (The following parameters is for reference

only)

① If U>13.2V, inspect the electrical system.

② If 12.5V<U<12.9V, the system is normal.

③ If 11V<U<12.4V, inspect charging system.

④ If U<11V, the battery is damaged or the charging system has trouble. Please inspect charging

system and battery.

4. Dismantlement and installation

1) Dismantlement

The ignition switch should be turned to the

“OFF” position.

① Disconnect the negative terminal.

② Dismount the positive terminal of battery and

the fixed bolts of battery pressure plate, and

then take off the pressure plate.

③ Take off the battery.

④ Take off the bracket of battery.

Fig. 3.2.002

Fig.3.2.001


140


① Bracket of battery

Check for erosion. If there is, clean with warm clean water.

② Battery harness

Check for erosion and damage. Replace if there is any.

3) Installation


Attention:

During connection, the anode terminal of battery should be connected first.

After installation, terminals may be smeared with mineral oil.


141

III. Starting System

1. System Description

Closed solenoid switch of starter provides a closed circuit between battery and starter. The starter is

connected with engine body for grounding. After the power supply and grounding are provided, the

starter can turn the crankshaft, and thus engine is started.


Components of Starter

1) Dismantlement

① Disconnect the negative terminal of battery.

Note: Before disconnecting the cathode terminal

of battery, pull off the starter key first.

Fig. 3.2.003

Fig. 3.2.004


142

② Disconnect the harness connector of starter.

③ Dismount the fixing bolts of starter, then take

off the starter.

2) Installation


Attention:

Be sure to tighten the nut of “B” port.

Fig. 3.2.005


143

3. Disassembly and Assemblage

1) Disassembly

Exploded View of Starter

1-Screw 2-Front support 3-Stop ring 4-Snap ring 5-Pinion 6-Gear ring 7-Solenoid switch 8-Plantery gear

9-Planetary gear 10-Ball 11-Gasket 12-Stator 13-Rotor 14-Electric brush retainer 15-Rear support

16-Fixing bolt

11

15

14

13

12

2

3

5

6

7

4 1

10

9 8

16


144

2) Check

① Solenoid switch

Before check, disconnect negative terminal of battery.

Disconnect the “M” port of starter.

a. Test electrical connectivity between “S” port

and switch body.

Replace solenoid switch if opened.

b. Test electrical connectivity between “S” port

and “M” port.

Replace solenoid switch if opened.

② Pinion

a. Visual inspection of the meshing gear teeth

If the teeth are worn or damaged, replace meshing gear (check teeth of fly wheel in this step).

b. Check the teeth of pinion

If the teeth are worn or damaged, replace pinion (check teeth of rotor shaft gear in this step).

c. Check whether the pinion locks in one direction while turns smoothly in the other direction.

If it is able to lock or turnable in both directions, or if there is abnormal resistance, replace.

Fig. 3.2.006

Fig. 3.2.007

Connecting from the power

supply

“M”

“M” end

Connecting from the power supply


145

③ Electric brush

Check brush wearing with a caliper. if

excessive worn, replace.

④ Electric brush spring

Depatch spring from the brush and use a

spring tension gauge to check tension

⑤ Electric brush retainer

a. Test insulation voltage between brush retainer

(positive) and bearings (negative) with an

ohmmeter. If broken, replace electric brush

retainer.

b. Check for electric brush smoothly moving.

If electric brush bracket is bent, replace. If the

sliding surface is dirty, clean.

⑥ Inspection of Stator

Check whether magnet is firmly fixed on the

stator; check for crack.

If the parts have any trouble, replace the

assembly.

Attention:

Please do not clamp the stator with a table

vice, nor hammer it.

Fig. 3.2.008

Vernier caliper

Electric brush

Electric brush

Electric brush

spring

Fig. 3.2.009

Fig. 3.2.010

Fig. 3.2.011 Magnet


146

⑦ Inspection of Rotor

a. Check connectivity between adjacent fillets

with ohmmeter.

If open, replace.

b. Check conductivity between each copper

plate and shaft of commutator with

ohmmeter.

If open, replace.

c. Check surface of commutator.

If it is rough, use # 500 sandpaper to lightly

sand with method shown in figure.

d. Check diameter of commutator.

Check with a caliper; if it is less than the

specified value, replace.

Fig. 3.2.012

Fig. 3.2.013

Sand paper

Vernier caliper

Commutator

Fig. 3.2.014


147

3) Assemblage

When assembling the starter, the bearing, the gear and the friction surface should be lubricated by

adding high temperature grease. And then conduct the following operations.

Gear clearance adjustment①

Push the pinion out with the magnetic switch

energized, meanwhile check the clearance

between the pinion and the thrust piece with a

feeler.

If the clearance is out of range, adjust by

using spacer.

Fig. 3.2.015

Fig. 3.2.016

Adjusting gasket

Stop block

Gear clearance

Pinion


148

4. Diagnosis flow chart of Common Troubles (if there is any abnormity found, disconnect negative

pole of battery at once.)

Inspection Flow Chart of Common Troubles of Starting System

Starter fails to stop. Replace the solenoid switch.

The engine fails to start.

Does engine run with revolving of crankshaft?

Does the starter run?

Does engine run normally?

Inspect ignition/fuel system.

Yes Yes

No

Inspect following items of

battery: 1. Charging condition

2. Connection of terminal 3.

Erosion of terminal.

No

A

Abnormal

Yes

Does the gear shaft run? Check pinion clutch.

Yes

Repair the starter. Normal

No

Check the reduction gear, armature and the gear shaft.

No

Check the fuse and the fusible wire.

Normal

Inspect following items of battery: 1. Charging condition 2. Connection of terminal 3.

Erosion of terminal.

Abnormal

replace.

Abnormal

1. Charge battery. 2. Repair poor connection and

eroded terminal of battery. A

Normal

Inspect circuitry of starting system.

Normal

Does magnet switch make noises during running?

Yes

Check the meshing condition of pinion and gear ring.

Abnormal

1. Adjust the displacement of pinion. 2. Inspect motion

mechanism of pinion. 3. Check the gear ring.

Abnormal

Repair.

Repair the starter. No

If wired as follows with no load, does

starter run?

Replace solenoid switch. Yes

Repair the starter. No


149

IV. Charging System


The generator is used to provide DC voltage to vehicle electric system and keep charged condition of

battery. The voltage output is controlled by IC adjuster.

The “B” port supplies electricity to vehicle electric system and charging power supply to battery. The IC

adjuster checks the input voltage at port 4 (“S” port) and thereby controls output voltage.

After the powered and grounded, the charging alarm light will be lit. When generator provides sufficient

voltage, the grounding circuit will be opened, while the charging alarm light will be turned off. If the

charging alarm light is still on with engine running, it has troubles.

2. Charging alarm light

If the following situations presents with generator working, the warming function of IC adjuster will be

actuated, and the charging alarm light will be turned on.

No voltage is produced or the voltage is high.


1) Dismantlement

① Disconnect the negative pole of battery.

② Disconnect harness connectors of generator.

③ Loosen the adjusting supporting nut on generator. Then adjust tension with the tension adjusting

bolt.

Tightening torque: generator adjustment nut: 22.5 ± 2.5 Nm

Generator supporting nut: 47±5 N.m

Fig. 3.2.017

Fig. 3.2.018


150

④ Dismount the belt of generator. Please refer to the “Drive Belt” section.

⑤ Take off the generator from the vehicle.

2) Installation

Install with reversed order of dismantlement.

Before installing the generator, please inspect tension of generator belt. Please refer to the “Drive

Belt”.

Attention:

Tighten the nut of “B” port. Tightening torque: 10-12 N·m

Fig. 3.2.019 Fig. 3.2.020


151


Exploded View of Engine

1-Lock nut 2-Belt pulley 3-Spacer 4-Front end cover 5-Front bearing 6- Bearing cap 7-Bolt 8-rotor

9-Rear bearing 10-Stator 11- gasket 12- commutator 13-Electric brush retainer

14-Guide sleeve of slip ring 15-Rear cover


152

1) Disassembly

Disassemble in the following order.

① Belt pulley

② Rear cover

③ Commutator assembly

④ Separate front and rear cover assembly.

Attention:

Be careful to avoid damage of stator assembly.

2) Check after disassembly

① Inspect of rotor

a. Resistance test

Resistance: Approximately 2.0-2.5 Ω

If it is beyond the standard range, replace.

b. Insulator test

If electrically continued, replace.

c. Inspect wearing condition of slip ring.

If it is beyond the standard range, replace.

② Carbon brush

a. Check carbon bush for smooth moving.

If not, inspect carbon brush support and clean

as required.

b. Check wearing condition of carbon brush.

If Limit is exceeded, replace brush.

Fig. 3.2.021

Fig. 3.2.022

Slip ring

The mark line of wearing limit of electric brush


153

③ Stator

a. Inspect continuity between terminals.

If not, replace.

b. Grounding test

If electrically continued, replace the stator.

3) Assembly

① Rear bearing

Attention:

The rear bearing can not be reused after being taken off. Please with new one.

Lubrication of rear bearing out race is not permitted.

② Installation of rear cover

a. Mount the carbon brushes assembly, adjuster

assembly and stator.

b. Push the carbon brushes with fingers to install them on the stator.

Attention:

Be careful to avoid damage of slip ring surface.

Fig. 3.2.025

Fig. 3.2.024

Fig. 3.2.023 Lead

Lead

Stator

core


154

5. Trouble Diagnosis for Charging System

Be sure that the battery has been sufficiently charged before test of generator. A 30 V volt meter and a

proper test probe should be used in test. Inspection chart is helpful for inspection of generator.

Check the fusible wire before starting up.

Use a battery fully charged.

Inspection Flow Chart of Charging System

Attention:

If the charging system has trouble but the test results suggest normal, inspect connection of

“B” port (Inspect tightening torque and voltage drop).

Inspect conditions of rotor coil, rotor slip ring, electric brush and stator coil. Replace failure

parts as required.

The ignition

switch is on.

The alarm

light is off.

The alarm

light is off.

The alarm light is

on.

The engine starts

with a rev of 1500

rpm.

The alarm light is

on.

The alarm light is

off.

The alarm light is

on.

Perform following

inspection: 1. rotor 2.

Slip ring of rotor 3.

Electric brush.

Change

damaged IC

regulator.

Conduct the

following check:

1. Rotor

2. Slip ring of

rotor 3. Electric

brush

The engine

runs at idle

speed.

The alarm light

is off.

The alarm light is

on.

Normal.

The engine rev is

2500 rpm.

Measure the

voltage of B port.

More than 16.0 V.

Less than 13.0 V.

Change the

damaged IC

regulator.

Conduct the following

check: 1. Rotor 2. Slip ring

of rotor 3. Electric brush 4.

Stator.

Change the

damaged IC

regulator or

diode assembly.

Normal.

Conduct following

check: 1. Bulb of

alarm light 2. Fuse of

alarm light .

Disconnect the

connector, and

ground the L-side

harness.

Alarm light: the “charging” alarm light in the

combined instrument.

Maintenance Manual for J2 Sedan Electronic Control System

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155

Chapter III Electronic Control System of Engine

Section I Precautions

I. Precautions of Supplemental Restraint System (SRS)

Using the SRSs including airbag and pretensioner of safety belt together with the front seat safety belt

can contribute to reduction of the risk of injury and hazard severity of driver and front passenger in case

of crash. For information of proper maintenance of the system, please refer to “Airbag” part of this

manual.

Caution:

All maintenance operation should be carried out by JAC authorized franchised stores in

order to avoid increasing risk of personal injury and death due to the SRS system failure.

Improper maintenances, including incorrect dismantlement and installation of SRS system,

may cause wrong action of the system resulting in personal injury and death.

For dismantlement methods bell spring (hair spring) and airbag controller, please refer to the airbag

section.

Besides operations described in this manual, no electrically testing equipment should be used to test

any circuit of airbag system. The air bag circuit harness can be identified by the yellow or orange

harness or harness connectors.

II. General Precautions

1. Only digital electric meter should be used to inspect the electronic control system.

2. JAC genuine components should be used during maintenance, otherwise it is impossible to

guarantee the normal operation of system.

3. Only unleaded gasoline should be used for maintenance and operation.

4. Specified maintenance and diagnosis procedure should be followed to perform maintenance.

5. The disassembly and dismantlement for the system components are prohibited during maintenance.

6. During maintenance process, the electronic elements (electronic control modules and sensors)

should be fetched and placed very carefully to avoid the falling down.

7. Keep strong awareness of environmental protection to effectively deal with waste of the

maintenance process.

III. Precautions in Maintenance

1. Temperature of electronic control module should never be higher than 80 during hot working

conditions simulation of trouble and other maintenance operations possibly resulting in the

temperature rising.

2. The electronic controlled injection system operates with high fuel pressure (approximately 350kPa).


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156

Even with engine stopped, there is high pressure in fuel pipelines. Therefore, the fuel pipe should

not be dismantled casually during the course of maintenance. In case that it is necessary to repair

fuel system, pressure in fuel system should be released before dismantlement of fuel pipe.

3. The dismantlement of fuel pipe and the replacement of fuel filter should be carried out by the

special personnel in well-ventilated area.

4. Power supply of electric fuel pump should be turn off before pump is removed from fuel tank in

order to avoid sparks that may cause fire. The fuel injection pump should not be test with dry state

or in water, otherwise its service life may be shortened. In addition, the positive and negative poles

of the fuel injection pump must not be reversed.

5. During inspection of ignition system, the sparking should be detected only when it is necessary and

the time should be as short as possible. The air throttle must not be opened during inspection;

otherwise copious unburned full may flow into the exhaust pipe, accordingly leading to the damage

of three-way catalyst.

6. The manual adjustment is unnecessary because the idling regulation is completed solely by the

electronic controlled injection system. The throttle limiting screw of throttle body has been adjusted

by the manufacturer in factory; the initial position must not be changed by users arbitrarily.

7. Terminals of battery must not be reversed, otherwise electronic components may be damaged.

Negative grounding is used in this system.

8. Battery cable should not be disconnected with engine running. Before welding on vehicle, cable on

negative and positive poles of battery, and all electronic components should be removed.

9. Do not test input and output signal of components by puncturing the insulator of wire.


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157

IV. Common tools for diagnose

Description of tool: diagnose tool of electronic controlled injection system

Function: reading/clearing DTC of electronic injection system, view data flow, test actions of parts, etc..

Description of tool: ignition timing indicator

Function: inspect ignition timing

Fig. 4.1.001

Fig. 4.1.002


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158

Description of tool: digital universal meter

Function: measure characteristic parameters such as voltage, current and resistance of electronic

injection system

Description of tool: vacuum gauge

Function: inspect air pressure of intake manifold

Fig. 4.1.003

Fig. 4.1.004


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159

Description of tool: cylinder pressure gauge

Function: inspect pressure in each cylinder

Description of tool: fuel pressure gauge

Function: inspect pressure of fuel system, determine working states of fuel pump and fuel pressure

regulator.

Fig. 4.1.005

Fig. 4.1.006


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160

V Precautions for On-board diagnose (OBD) system of engine

The electronic control module (ECM) has an OBD system. The malfunction indicator lamp (MIL) of

OBD system will be lit to indicate the driver that there is malfunction caused by aging of the exhaust

system.

Be sure to turn the ignition switch to OFF position and disconnect the cable of battery negative

poles before any repairing or inspection. The open circuit or short circuit of related switch, sensor

and solenoid valve may make the MIL lit.

After the operation, be sure to insert connectors and lock them firmly. Loose (unlocked) connectors

may result in the open circuit, accordingly making the MIL lit. (Make sure that there is no water,

grease and filth on the joint and port is not bent).

After the operation, be sure to route and fix the harness correctly. The interference between support

and harness etc. may result in short circuit, accordingly making the MIL lit.

After the operation, be sure to connect the rubber pipe properly. The failed connection of the rubber

pipe may cause lighting of MIL because of failure of the EVAP system and fuel injection system

etc.

Be sure to clear any uneffective DTC from ECM before transferring vehicle to user (the repair is

done).

Be sure to use the 12V battery as the power supply.

Never disconnect cable of battery with engine running.

Be sure to turn ignition to OFF position and disconnect cable of battery before connecting or

disconnecting any ECM harness connectors. Otherwise the ECM may be damaged, because even if

the ignition is turned to OFF position, the ECM still has 12V voltage.

Turn the ignition switch to OFF position and disconnect the connecting wire cable of storage

battery cathode before dismounting the any components.

Don’t disassemble the ECM.

If one of the battery cable is disconnected, memory of ECM will return to the initial value. And the

ECM may start to control itself with initial value. When battery is disconnected, the engine will

operate a little differently, which doesn’t mean any trouble. Don’t replace any components because

of a little change.

Battery

Fig 4.1.007


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161

When connecting the ECM harness connectors, push the deflector rod (1) downward mostly to lock

securely.

When Inserting the contact pin into the ECM

or pulling it out, be aware to avoid damaging

contact pin port (bent or broken). When

connecting the contact pin, make sure that the

contact pin port of ECM is not bent or

broken.

Connect the harness connectors of ECM

firmly. Poor connection may cause extremely

high (fluctuation) voltage on the coil and

capacitor, accordingly resulting in damage of

IC.

The harness of the electronic control system of engine should be remained for a length of at least

10cm from the joint in order to avoid any trouble of the electronic control system of engine caused

by receiving the exterior noise signal and decreasing the operation of IC etc.

Keep the parts and harness of the electronic control system dry.

Inspect ECM with port and reference value to assure the normal function of ECM before replacing.

Even the very little leakage in the intake system may lead to the severe trouble.

Don’t swing or vibrate the camshaft position sensor (phase) or the crankshaft position sensor

(position).

Perform DTC validation procedures or the whole function inspection after conduction of trouble

diagnosis. If repair is finished, DTC should not be seen in the validation procedures. Overall

function inspection should obtain a good result after repair completed.

When measuring the ECM with the circuit tester, never make two measuring devices contacted. If

the probes touch occasionally, the short circuit may be cause and the power transistor of ECM may

be damaged.

During measurement of input/output voltages, the grounding port must not be used. Otherwise the

transistor of ECM may be damaged. Ports other than the ECM may be used for gounding.

Fuel pump must not be used without fuel in pipes.

Fig 4.1.008

Broken

Bent


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162

Tighten clamp of fuel hose to specified torque.

Don’t step on accelerator pedal when starting

the vehicle.

Don’t increase the speed of engine

immediately after starting the vehicle.

Don’t speed up before shutting down the

engine.

Fig 4.1.009


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163

Section II Structural Principle and Inspection of Engine Control System

I. System Description

Generally, the engine management system is mainly composed of three parts, namely sensors,

micro-processor (ECU), and actuators, to control the intake volume, fuel injection amount, and ignition

advance angle during the running of the engine. The basic structure is shown in the figure below:

Basic Structure of Engine Control System

In the engine electronic control system, the sensors are functioned as input parts to measure all kinds of

physical signals (temperature, pressure, etc.) and convert to corresponding electric signals, the ECU is

functioned to receive the input signals from sensors, calculate and process as per preset programs,

generate corresponding control signals, and output to power drive circuits, and the power drive circuits

execute different actions by driving corresponding actuators and control the engine to run as per preset

control strategy. At the same time, the malfunction diagnosis system of ECU monitors various

components and control functions in the system. Once a malfunction is detected and confirmed, the

system will save the malfunction code and activate the “Limp home” function. Upon the detection that

the malfunction is resolved, the system will resume to normal values.

The greatest characteristic in the electronic control system of the M7 engine is the adoption of

torque-based control strategy. The torque-based control strategy is mainly intended to link a great

amount of different control objectives. This is the sole method to integrate flexibly all kinds of functions

into different variants of ECU depending on the engine and vehicle models. The structural diagram of

the electronic control system is shown as below:

Engine

Actuators Sensors Diagnosis Diagnosis

Product manufactured by

UAES

Electric fuel pump ansd brakckt assembly

Diagnosis interface

Stepping

motor

Speed sensor

Throttle position sensor

Three-way catalytic converter

Oxygen sensor

Ignition coil

Phase

sensor

Fuel dis

trib

uto

r

pip

e a

ssem

bly

Fuel pressure regulator

Intake

pressure/

temperature

sensor

Fuel filter

Fuel tank

Knock

sensor

Fuel injector

Water temperatrue

sensor

Carbon canister control valve

Carbon canister

Throttle body assembly


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164

Illustration of Engine Control System

Note: This diagram is the control diagram, if the sensor location doesn’t match with

physical parts, actual conditions should prevail.

II. Multiple-point Fuel Injection System


Multiple-point fuel injection (MPI) system comprises of the sensor detecting engine operation and the

electronic control module (ECM).

The system is controlled based on signals from these sensors; actuators operate under control of the

ECM. ECM functions include fuel injection control, idle control and ignition timing control etc. and

some trouble diagnosis means for simplifying the troubleshooting in case of trouble.

2. Input/Output Signal

List of Input/Output Signal

Sensor Input Signal of

ECM ECM Function Actuator

Hall sensor Engine speed

Piston position


Intake quantity

Oxygen sensor Oxygen

concentration in

exhaust

Throttle opening sensor Throttle opening

Knock sensor Knock of engine

Air conditioner switch Air conditioner

pressure

Wheel speed sensor Vehicle speed

Coolant temperature sensor Coolant temperature

Control fuel

injection and

mixing

Fuel injector

3. Starting Control

Special measures should be used to control the air flow, fuel injection and ignition timing during starting.

At the beginning of starting, air in the intake manifold is still and the internal pressure of the intake

manifold is ambient air pressure. Throttle closed and the electronic throttle is designated as a fixed

parameter depends on temperature. In similar process, a specific "injection timing" is designated as the

initial injection pulse. Fuel injection amount varies according to engine temperature in order to promote

fuel film formation on intake manifold and cylinder walls; thus, when the engine reaches a certain speed,

mixture should be thicker. Once the engine starts to run, the system immediately begin to reduce the

mixture concentration At end of starting cycle, the starting enrichment function will be completely


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165

cancelled. In starting work conditions, spark advance are also adjusted and vary with the engine

temperatures, intake air temperatures and engine speeds.

4. Warming-up and Heating Control of Three-way Catalyst

With engine started at low ambient temperature, intake quantity of cylinder, fuel injection and electronic

ignition are all adjusted to compensate the higher requirement of the engine torque; this process

continues until the temperature is proper. During this stage of running, the most important factor is the

quick heating of the three-way catalyst, for fast transition to the three-way catalyst functioning can

markedly reduce the emission. Under this operation condition, the “heating three-way catalyst” may be

performed by postpone the ignition advance angle properly to take advantage of the exhaust gas.

5. Acceleration/Deceleration and Back-tow Fuel Cut Control

Part of the fuel injected to the intake manifold will not reach the cylinder in time to participate

follow-up combustion stroke. Instead, it forms a film on intake manifold wall. With increasing of load

and injection duration extension, fuel stored in the film will build up dramatically. When the throttle

opening increases, part injected fuel will be absorbed by the film. Therefore, corresponding amount of

fuel must be added for compensation and to prevent the mixture from thinning during acceleration.

Once load factor is reduced, the additional fuel contained in the fuel film on intake manifold wall will be

re-released, and then it is necessary to reduce the injection duration accordingly during acceleration

course. Back-tow and towing operation condition refers to conditions that the power supplied by the

engine at the fly wheel is negative value. In this case, the engine friction and pumping gas loss can be

used to make vehicles slow down. In back-tow or towing operation condition, fuel injection is cut off in

order to reduce the fuel consumption and the emission, more importantly, the three-way catalyst can be

protected correspondingly. Once engine speed decreases to the specific fuel supply recovery speed

above idling, the fuel injection system will re-supply. In fact, ECM program has a rotation speed

recovery range which depends on the changes of such parameters as engine temperature, dynamic

change of engine speed, which can also prevent the engine speed from dropping to the specified

minimum through calculation. Once the fuel injection system re-supplies fuel, the supplemental fuel

will be supplied by using the initial injection pulse and the fuel film on the intake manifold wall will be

formed. After resumption of fuel injection, torque-based control system makes the increase of engine

torque slow and steady (smooth transition).

6. Idle Control

At idle speed, the engine does not provide torque to the fly wheel. To ensure the engine running stably at

the lowest possible idle speed, the closed-loop idle speed control system should keep the balance

between the generated torque and the "power consumption" of engine. The necessary power should be

generated with idling speed to meet the load requirements of all aspects, including those come from

internal friction from the engine crankshaft and valve mechanism, as well as the auxiliary components,

such as coolant pump. The system is based on the torque-based control strategy, which determines

required output torque of engine to maintain the required idle rotation speed under any operating

conditions with a closed-loop idle speed control strategy. The output torque increases with decreasing of

engine speed and decreases with rising of engine speed. The system request greater torque to response to

the new "disturbance factors", such as the switch of the air-conditioning compressor. With low engine

temperature, it is necessary to increase the torque to compensate the greater internal friction loss and/or


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166

maintain higher idling speed. Sum of all these required output torque is delivered to the torque

coordinator to carry out the calculation to get the corresponding intake density, gas mixture composition

and ignition timing.

7. λClosed-loop Control

Post treatment of three-way catalyst is an effective way to decrease the concentration of hazardous

substance in the exhaust gas. The three-way catalyst can decrease the HC, CO and NOX by 98% or more

and transform them into H2O, CO2 and N2. However this high efficiency can only be achieved in a very

narrow range near the excessive air factor of engine λ=1. The objective of the λ closed-loop control is to

ensure the gas mixture concentration at this range, thus, the closed-loop control system is used to get

this target. λ closed-loop control system functions only with oxygen sensor equipped. Oxygen sensor

can detect oxygen content of the exhaust gas at three-way catalyst side. Rarefied gas mixture (λ> 1)

produces a sensor voltage of about 100mV and the concentrated gas mixture (λ <1) produces a sensor

voltage of about 900mV. In case of λ=1, the sensor voltage has a jump. λ closed-loop control responds

to the input signal (λ>1= too thin mixture, λ<1= too thick mixture) to revise the control variable and

produce a correction factor as a multiplier to correct the fuel injection duration.

8. Evaporation Emission Control

Due to transfer of the external radiation heat and oil return heat, the fuel in tank is heated to form vapor.

According to limit of evaporative emission regulation, it is not permitted to exhaust the vapor containing

large quantity of HC composition directly into the atmosphere. The fuel vapor in the system is collected

with an active carbon canister through the conduit and flushed into the engine at appropriate time to

participate combustion. Flushing flow is controlled by the carbon canister control valve of ECM. The

control functions only when the λ closed-loop control system is running under the closed-loop

condition.

9. Fuel Injection Control

The fuel injection timing and impulse width is controlled to provide the best mixing of air/fuel

corresponding to the ever-changing operation condition of engine. The fuel injector is installed at the

inlet of every cylinder. The fuel is drawn from tank by fuel pump and delivered to each fuel injector.

Normally, each cylinder has one fuel injection operation with two revolutions of crankshaft. Injection

sequence of cylinders is 1-3-4-2.

10. Ignition Timing Control

The primary current to the ignition coil is controlled by connecting and disconnecting the power

transistor of primary ignition circuit to regulate the ignition timing so that the best ignition timing can be

provided according to operating conditions of engine. Ignition timing is determined by the ECM

according to the engine speed, intake quantity, coolant temperature and atmospheric pressure.

11. Self-diagnosis Function

When abnormal situation is detected by the sensor or actuator related to the exhaust control, the alarm

lamp of engine (inspection lamp of engine) lights up to inform the driver. DTCs (diagnose trouble code)

corresponding of this abnormal situation will be set in these conditions. The RAM data inside the ECM


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167

related to the sensor and actuator can be read with the diagnosis apparatus, and the actuator may be

driven forcibly in some cases.

12. Other Control Functions

1) Fuel Injection Pump

With relay connected, the fuel injection pump will be energized when the crankshaft starts to rotate or

with engine running.

2) Fan Relay Control

The speeds of the radiator fan and condenser fan is controlled with the engine coolant temperature,

vehicle speed and air conditioner switch signal (AC).

III. On-board Diagnosis System

1. Description

On-board diagnosis system (hereinafter referred to as OBD system) is the diagnosis system integrated in

the engine control system to monitor the trouble components affecting the emission as well as the main

function state of the engine. It is capable of identifying, storing and showing the trouble information

through the self-diagnosis malfunction indicator lamp (MIL).

2. Trouble Information Record

Electronic control module constantly monitors the sensor, actuator, associated circuit, malfunction

indicator lamp (MIL) and battery voltage etc. as well as even the electronic control module itself, and

carries out the credibility detection for the output signal of sensor, the drive signal of actuator and the

internal signal (such as λ closed-loop control, coolant temperature, idling speed control and battery

voltage control etc.). Once a trouble is found in some link or a signal value is incredible, the electronic

control module immediately sets the trouble information record in RAM memory. Trouble information

record is stored in form of DTC and shown based on the order in which the troubles present.

The troubles can be divided into “steady-state trouble" and "sporadic trouble" according to their

occurrence frequencies (for example, because of short term open circuit of harness or poor contact of

connector).


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Schematic Diagram for Malfunction Diagnosis of Electronic Injection System

3. Control strategy of malfunction indicator lamp

1) When no malfunction is present:

The malfunction indicator lamp lights up after the ignition switch is turned on (ON) and then goes

out after 4s.

If the engine is started within 4s, the malfunction indicator lamp goes out upon detection of speed

signal.

After the K-line is grounded for more than 2.5s, the malfunction indicator lamp will flash at a

frequency of 2Hz.

2) When a malfunction is present:

The malfunction indicator lamp will be always on after the ignition switch is turned on (ON).

After the engine is started, the malfunction indicator lamp will go out upon detection of speed

signal. If the malfunction indicator lamp in question is defined as ON mode in the malfunction

category, the malfunction indicator lamp will be always on after the corresponding conditions are

met.

4. Inspection steps

1) For the vehicles with OBD function, inspection should be carried out always with steps below:

OBD Inspection Steps

1. Connect the diagnosis equipment to the

diagnosis connector to put through it.

Function diagnosis

Electronic control unit

Data collection

Function diagnosis

Control command

Actuators Sensors

Engine


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169

2. Turn on “ignition switch”.

3. Read the trouble information (trouble code,

freeze frame): inquire in maintenance manual

to confirm the trouble component and type:

draw up maintenance solution with trouble

information and experiences.

4. Remove the trouble.

5. Clear memory: run the vehicle properly

following the corresponding trouble diagnosis

conditions: read trouble related information

and confirm the clearing of the trouble.

2) Connection of Diagnosis apparatus:

The “K” line protocol and ISO9141-2 standard diagnosis joint are adopted for the system as shown in

the figure.

Standard Diagnosis Connector

This standard diagnosis joint is connected on the harness of engine steadily. The pins 4, 7 and 16 of the

standard diagnosis joint are used for engine electronic control system. The pin 4 of the standard

diagnosis joint is connected to the grounding wire: pin 7 is connected to the pin 15 of ECM, that is, the

“K” data line of the electronic control system of engine; pin 16 is connected to battery negative pole.


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170

5. List of Common Control System Malfunction Codes of ECU

1.0 Table of Common Malfunction Codes for UAES Control System of

3-Cylinder Engine

DTC Information Introduction of Malfunction Codes (UAES)

P0030 Open-circuit of upstream oxygen sensor heating control circuit

P0031 Short-circuit of upstream oxygen sensor heating control circuit to ground

P0032 Short-circuit of upstream oxygen sensor heating control circuit to power supply

P0036 Open-circuit of downstream oxygen sensor heating control circuit

P0037 Short-circuit of downstream oxygen sensor heating control circuit to ground

P0038 Short-circuit of downstream oxygen sensor heating control circuit to power supply

P0053 Inappropriate heating internal resistance of upstream oxygen sensor

P0054 Inappropriate heating internal resistance of downstream oxygen sensor

P0105 No signal variation of air intake pressure sensor (Frozen)

P0106 Inappropriate air intake pressure sensor

P0107 Short-circuit of air intake pressure sensor to ground

P0108 Short-circuit of air intake pressure sensor to power supply

P0112 Low signal voltage of air intake pressure sensor

P0113 High signal voltage of air intake pressure sensor

P0117 Low voltage of engine coolant temperature sensor circuit

P0118 High voltage of engine coolant temperature sensor circuit

P0122 Out-of-lower-limit of throttle position sensor circuit voltage

P0123 Out-of-upper-limit of throttle position sensor circuit voltage

P0130 Inappropriate upstream oxygen sensor signal

P0131 Low upstream oxygen sensor signal circuit voltage

P0132 High upstream oxygen sensor signal circuit voltage

P0133 Aged upstream oxygen sensor

P0134 Malfunction of upstream oxygen sensor circuit signal

P0136 Inappropriate downstream oxygen sensor signal

P0137 Low downstream oxygen sensor signal circuit voltage

P0138 High downstream oxygen sensor signal circuit voltage

P0140 Malfunction of downstream oxygen sensor circuit signal

P0170 Inappropriate closed-loop control self-learning of off-line testing air-fuel ratio

P0171 Thin closed-loop control self-learning of off-line testing air-fuel ratio

P0172 Thick closed-loop control self-learning of off-line testing air-fuel ratio

P0201 Open-circuit of 1# fuel injector control circuit



P0261 Short-circuit of 1# cylinder fuel injector control circuit to ground

P0262 Short-circuit of 1# cylinder fuel injector control circuit to power supply




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P0300 Detection of misfire in various cylinders

P0301 Detection of misfire in 1# cylinder



P0321 No detection of missing tooth BM signal after certain angle rotation of crankshaft

P0322 No pulse signal of speed sensor (open-circuit or short-circuit)

P0327 Low voltage of knock sensor signal circuit

P0328 High voltage of knock sensor signal circuit

P0340 Inappropriate installation location of phase sensor

P0341 Poor contact of phase sensor

P0342 Short-circuit of phase sensor to ground

P0343 Short-circuit of phase sensor to power supply

P0420 Aged oxygen storage capacity of three-way catalytic converter (out-of-limit of emission)

P0444 Open-circuit of carbon canister control valve control circuit

P0458 Low voltage of carbon canister control valve control circuit

P0459 High voltage of carbon canister control valve control circuit

P0480 Open-circuit of cooling fan relay control circuit (low speed)

P0481 Open-circuit of cooling fan relay control circuit (high speed)

P0501 Inappropriate vehicle speed sensor signal

P0506 Lower idling control speed against target speed

P0507 Higher idling control speed against target speed

P0508 Short-circuit of stepping motor drive pin to ground

P0509 Short-circuit of stepping motor drive pin to power supply

P0511 Open-circuit of stepping motor drive pins

P0560 Inappropriate system battery voltage signal

P0562 Low system battery voltage

P0563 High system battery voltage

P0602 Programming error of electronic control unit

P0627 Open-circuit of fuel pump relay control circuit

P0628 Short-circuit of fuel pump relay control circuit to ground

P0629 Short-circuit of fuel pump relay control circuit to power supply

P0645 Open-circuit of A/C compressor relay control circuit

P0646 Short-circuit of A/C compressor relay control circuit to ground

P0647 Short-circuit of A/C compressor relay control circuit to power supply

P0650 Malfunction of malfunction indicator lamp circuit

P0691 Short-circuit of cooling fan relay control circuit to ground (low speed)

P0692 Short-circuit of cooling fan relay control circuit to power supply (low speed)

P0693 Short-circuit of cooling fan relay control circuit to ground (high speed)

P0694 Short-circuit of cooling fan relay control circuit to power supply (high speed)


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P1651 Malfunction of SVS lamp drive circuit

P2177 Out-of-upper-limit of air-fuel ratio closed-loop control self-learning (Medium load zone)

P2178 Out-of-lower-limit of air-fuel ratio closed-loop control self-learning (Medium load zone)



P2270 Aged downstream oxygen sensor



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IV. Engine Trouble Diagnosis

1. Trouble diagnosis general for engine control system

In case of failure with Engine Electronic control system components (such as sensor, ECM, injector),

fuel may be cut off or insufficient fuel will be supplied resulting in following conditions:

a. Starting hardship or failure of engine

b. Unstable idle

c. Poor drivability

If any of these situations occurs, first of all, carry out the regular inspection including the basic

inspection of engine (ignition system trouble and correct adjustment of engine etc.). Then inspect the

sub-assemblies of the electronic control system with trouble diagnose apparatus.

Attention:

Before dismantling or installing any component, read the DTC at first and then disconnect

battery negative poles.

Before disconnecting battery cables, firstly turn off the ignition switch. If battery cable is

disconnected with engine rungin or ignition at ON position, ECM may be damaged.

The harness between the ECM and sensor should be shielded by the grounding wire connected to

the vehicle body in order to prevent the interference from the ignition system and radio. If fails,

the harness should be replaced.

When checking the charging state of engine, don’t disconnect the negative pole of battery to

prevent damage of ECM.

When using the outside charger to charge the battery, it is necessary to disconnect battery cable

to prevent damage of ECM.


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2. Trouble Diagnosis Flow Chart

The check starts

1. Acquire the symptom information

Ask the user for more information associated with symptom

2.Check the DTC

Check DTC and print DTC and freeze frame

data, inspect related maintenance record

3.Recognize the symptom

Attempt to diagnose the

symptom described by the user.

User described the

symptom and the

apparatus displays DTC

5. Implement the confirmation steps of DTC.

User did not

describe the

symptom, but

apparatus

displays the

DTC.

4. Recognize the symptom

Attempt to diagnose the symptom

described by the user.

User described the

symptom and

apparatus did not

show DTC

6. Implement the basic check.

10. Check the troubled component through the

diagnosis steps

9. Use the trouble

symptom table to check

troubled system

8. Check the troubled

component

7. Run the trouble diagnosis &

check mode

11. Repair or replace the troubled components

12. Final check

Confirm no symptom found

Implement the “DTC confirmation steps” again,

and be sure to repaire the trouble properly.

Ab

no

rma

l (DT

C d

ete

cte

d)

Normal

The check ends

No troubled component found

Within the scope of technical parameters

Beyond the scope of the technical parameters

Inspect with trouble diagnosis apparatus

Troubled component

found

Abnormal (symptom

still exists)

Do not use the trouble diagnosis apparatus


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3. Trouble Symptom Check Table

List of Trouble Symptom Inspection

Symptoms Check Order No.

Unable to communicate with all the systems 1 Unable to communicate with

diagnosis apparatus Unable to communicate with ECM only 2

Engine alarm lamp failed to light up immediately after the

ignition switch is turned to ON. 3 Engine alarm lamp and

corresponding components Engine alarm lamp keeps bright 4

No initial ignition (unable to start) 5

There is initial ignition but it burns incompletely (unable to

start) 6 Start

Too long starting duration (unable to start normally) 7

Unstable idle (fluctuant idle speed and hunting) 8

High idle speed (abnormal idle speed) 9 Idle Stability (abnormal idle speed)

Low idle speed (abnormal idle speed) 10

The engine stops at the idle when it is cold. (stop with

deceleration) 11

The engine stops at the idle when it is hot. (stop with

deceleration) 12

The engine stops at the start. (stop with acceleration) 13

Idle Stability (engine stops)

The engine stops with deceleration 14

Vehicle surge, drop or instability of vehicle speed 15

Shock or vibration during acceleration 16

Shock or vibration during deceleration 17

Poor acceleration 18

Surge 19

Driving

Knock 20

Fail to stop engine 21

High concentration of CO and HC at the idle operation 22

Low voltage of alternator 23

Abnormal idling speed when starting the air conditioner 24

Abnormal operation of fan 25


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4. Symptom List

Symptom List

Items Symptoms

Failure of starting Starter drags the engine, but there is no combustion in cylinder and the engine

does not start.

Extinguishment after

combustion There is combustion in cylinder, but the engine extinguishes immediately.

Start

Hard to start Engine starts after the crankshaft rotates a while.

Hunting Engine does not maintain a constant speed and the speed changes within range

of idle speed.

Fluctuation of idle Usually, it can be determined with the swing of tachometer pointer and the

vibration transferred to the steering wheel, selector rod and body etc.

Incorrect idle Engine is running idly at the incorrect rotation speed.

Extinguishment of engine

(with deceleration)

When releasing the accelerator pedal, no matter whether the vehicle is moving,

the engine stops.

Stability

of idle

speed

Extinguishment of engine

(with acceleration) When the accelerator pedal is depressed or being depressed, the engine stops.

Vehicle surge, drop of

speed

The phenomenon of “vehicle surge” refers to that the vehicle speed (rotation

speed of engine) responds slow when there is a need to accelerate and depress

down the accelerator pedal at the current vehicle speed or the temporary decline

of vehicle speed (rotation speed of engine) during acceleration.

Poor acceleration

Poor acceleration refers to that the vehicle is unable to acquire acceleration with

the opening of air throttle even with stable acceleration; or refers to the

disability to reach the maximum vehicle speed.

Instability When firstly depressing down the accelerator pedal to speed up, engine speed

increases slowly.

Shock There is huge shock or vibration of engine with accelerating or decelerating.

Surge There is repeatedly forward surge when traveling with constant or variable

speed.

Driving

Knock There is a strong voice like the hammer against the cylinder wall during the

driving which is harmful to driving.

Parking Keep running(fail to

stop)

5. General Trouble Inspection

Engine trouble inspection should begin with the basic system. In case of starting failure, unstable idle or

insufficient fuel supply, begin the following basic systems:

a. power supply: battery, fusible link and fuse wire

b. Grounding

c. Fuel supply: fuel pipe, fuel filter, fuel pump

d. Ignition system: spark plug, high tension line, ignition coil.

e. Emission control system: Leakage of vacuum system.

f. Others: ignition timing and idle.

The trouble of electronic control system of engine is generally caused by poor contact of the harness

connector. All the harness connectors should be checked to verify whether they are connected correctly.


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6. Inspection of Idling Speed

1) Conditions

Attention:

Check the regular items including spark plug, fuel injector and compression pressure of the

cylinder at beginning of inspection.

① The engine coolant temperature is 80-95 .

② Lamps, electronic fan and all the accessories are turned off.

③ Shiftlever is at neutral position.

④ The steering wheel is at center (equipped with power steering system).

2) Connect the diagnosis apparatus.

3) Start engine and run it at the lowest idle speed.

4) Run engine for over 5s with speed of 2000-3000 rpm and then make the engine operate for 2min at

the idle speed.

5) Read idling speed (750±50r/min).

7. Fuel Pressure Test

Attention:

Before disconnecting the fuel pipeline, it is necessary to release the fuel pressure inside the fuel

pipeline to eliminate the danger.

The O-ring should always be used to keep the seal of the connecting joint of fuel hose.

Don’t operate the electrical system during inspection.

Note: Prepare a container under fuel pipe to avoid the fuel spillage when pipes disconnected.

1) Dismount the nut at fuel pressure inspection port on the guide rail of fuel injector.

2) Connect fuel pressure gauge.

3) With ignition switch at “ON” position, check for fuel leakage.

4) With engine running with idling speed, check for the fuel leakage.

5) Take down reading of fuel pressure gauge.

Fuel pressure: 350KPa

Attention:

Don’t check fuel pressure with system operating.


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During inspection of fuel pressure, always to make sure whether there is fuel leakage in fuel

pipeline.

7) If the measured fuel pressure is more than the standard value, analyze the possible reasons referring

the following table and repair as required.

Fuel System Trouble Diagnosis Table 1

Phenomenon Possible Cause Troubleshooting

Blockage of fuel filter Replace the fuel filter

Too low fuel pressure Damaged fuel pump or poor sealing of fuel pressure

regulator resulting in fuel leakage at returning side Replace fuel pump

Cementation of fuel pressure Replace fuel pump

Too high fuel pressure Blockage or bend of fuel return pipe

Repair or replace fuel

pipe

8) Turn off engine and check the changes of fuel pressure gauge reading for 5min. If the reading drops,

observe the reduction rate. Referring to following table to analyze and eliminate the trouble.

Fuel System Trouble Diagnosis Table 2

Phenomenon Possible Cause Troubleshooting

Fuel pressure drops slowly after engine

stopped Leakage of fuel injector Replace injector

Fuel pressure drops completely after engine

stopped. Trouble of fuel pump Replace pump

9) Reduce the pressure in fuel pipeline.

10) Disconnect the fuel pressure gauge and install the inspection port nut.

11) Check for fuel leakage with following steps.

① Turn the ignition switch to the "ON" position (with engine stopped), and then check for leakage at

the joint of the fuel pipeline.

② Start the engine and increase speed, inspect whether there is leakage at joint of fuel system.


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Section III Structural Principle and Inspection of Engine Electronic Components

I. Intake Manifold Absolute Pressure (MAP/MAT) Sensor

1. Description

1) Intake absolute pressure sensor (MAP) is a pressure sensitive variable resistor. Diaphragm inside of

sensor is connected with a magnet core placed through the coil. When intake pipe pressure changes,

the diaphragm will drive the core to movement and thus change output voltage of sensor .With

sensor output voltage, ECU can determine engine intake volume, with which and reference to other

signals, injection volume control is achieved. .MAP sensor is also used to measure atmospheric

pressure during starting; under certain conditions, it allows the ECM to be adjusted automatically at

different altitudes. ECM provides 5V voltage to MAP sensor and receives voltage signal by the

signal line. The sensor is grounded with a wire from its variable resistor. MAP sensor input signal

affects ECM fuel output and ignition timing control.

2) Intake temperature sensor element is a thermistor with negative temperature coefficient (NTC). Its

resistance increases with the intake air temperature decreases. Engine ECU detects intake air

temperature changes via a contrast circuit.

2. Installation Position

Installed on the back of throttle

3. Circuit Diagram

Pin 19: 5V voltage signal

Pin 59: Manifold pressure sensor signal

Pin 40: Power ground

Pin 25: Intake air temperature sensor signal

Operating voltage: 5 ± 0.1V

Fig. 4.3.001

Inta

ke

pre

ssu

re/

tem

pe

ratu

re

se

nso

r

5V power supply 1

Sensor grounding


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4. Diagnosis

Sensor short circuit (to ground, to power supply);

Sensor circuit open;

Sensor detects the intake pressure exceeds the upper limit;

Sensor detects the Intake pressure exceeds the lower limit;

5. Trouble Solution

Mainly check the 4 connections of the sensor and connection with ECU for short circuit, open

circuit;

Check sensor detection holes for blockage.

Whether a short circuit, open circuit, grounding problem exists in sensor wiring harness

Whether sensor is highly impacted resulting in sensor failure.

Operating pressure range: 12.5kPa - 115kPa

Operating temperature range: -40 - 125


1) Dismantlement

① Disconnect the wire harness connectors of intake

manifold pressure & temperature sensors.

Attention:

Make sure that the ignition switch is at “Off”

position.

② Disassemble the fixing screws of the intake

pressure/temperature sensor with crosshead screw

driver, remove the sensor.

2) Installation


Fig.4.3.002

Fig.4.3.003


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181

Apply a small amount of engine oil on seal ring of sensor in order to facilitate the installation.

Make sure that adhesive of sensor and intake manifold is well, tighten the self-tapping screw

Verify reliable installation of wire harness connector.

II. Engine Coolant Temperature (ECT) Sensor

1. Instruction of Parts

The engine coolant temperature sensor measures the engine coolant temperature and sends the signal to

the ECM for control of ignition timing and fuel injection pulse width during start, idling, and normal

running. It adopts one negative temperature coefficient thermistor, of which the resistance reduces

following the increasing of the temperature. Depending on the voltage output of the sensor, the ECM

judges the temperature of coolant and sends gas mixture with best air-fuel ratio to the engine.

2. Installation Position of Element

See figure right for installation positions.

3. Wiring Diagram

Pin 40: 5V Grounding

Pin 41: Cooling water temperature signal output

Fig. 4.3.004


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4. Diagnosis

Water temperature signal higher than the limit;

Water temperature signal lower than the limit;

Water temperature sensor short circuit, open circuit.

Room temperature resistance data: 2.5 ± 5%kΩ

5. Trouble Solution

It mainly checks the connections between wires of sensor and ECU and between wires of sensor

and instruments for presence of short-circuit and open-circuit.

Short circuit, open circuit, grounding problems between sensor harness.

Grounding: poor grounding easily lead to excessively high engine water temperature indication;

Operating voltage: 5V;

Operating temperature range: -40 - 135


Characteristic parameters (standard)

Coolant temperature sensor


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1) Dismantlement

① Discharge coolant from radiator. Please refer to

"Change Engine Coolant".

② Disconnect the wire harness connector of the

engine coolant temperature sensor.

③ Dismantle the engine coolant temperature sensor.

2) Installation

Be aware of following precaution to install with steps contrary to dismantlement.

Apply surface sealant on threaded part of sensor and tighten with specified torque. Tightening

torque :16-24N. M

Verify reliable installation of wire harness connector.

With engine idling，visually inspect coolant leakage.

III. Throttle Position Sensor


This sensor is one angle sensor with linear output characteristic and is composed of two arc sliding

contact resistors and two sliding contact arms. The hinges of the sliding contact arms are coaxial with

the throttle shaft. A 5V supply voltage US is applied onto two sides of the sliding resistors. At the

rotation of the throttle, the sliding contact arms rotate as well to move on the sliding contact resistors

and output the potential UP of the contact as voltage output. Therefore, it’s actually a rotation angle

potentiometer that outputs a voltage signal in proportional to the throttle position.

Fig. 4.3.005


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184


It’s installed on throttle body.

3. Wiring diagram of throttle position sensor

Pin18: 5V power supply

Pin26: Throttle position sensor signal

Pin39: 5V grounding

4. Diagnosis

Poor acceleration, etc.

5. Solutions

Mainly inspect sensor and ECU wiring harness for short circuit, open circuit, grounding problems;

Shift the multimeter to Ohm measurement scale and connect two probes of the multimeter to 1# and

2# pines of the sensor respectively to measure the resistance. The measurement at ambient

temperature shall be 2kΩ±20%. Connect two probes to the 1# and 3# pins respectively and rotate

Fig. 4.3.006

Throttle Position Sensor


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185

the throttle. The resistance measurement shall vary linearly following the opening of the throttle.

The measurement on 2# and 3# pins shall be on the contrary.

Note: While observing the variation of resistance, pay attention to observe for presence of high

resistance leap.

Operating temperature: -40 - 125 ;

6. Dismantlement and installation of throttle

position sensor

1) Dismantlement

① Disconnect the wire harness connector of air

throttle position sensor.

Note: Be sure that the ignition switch is at the

“Off” position.

② Remove the screws of throttle position sensor

and remove the sensor.

2) Installation

Be aware of following to install with steps contrary to dismantlement.

Verify that the of the wire harness connector is inserted securely.

Tighten self-tapping screw.

IV. Crankshaft Position Sensor

1. Component Description

The crankshaft position sensor is used to provide the engine speed information and crankshaft top

Fig. 4.3.07

Fig. 4.3.08


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186

dead center information in the ignition system. It’s composed of a permanent magnet and a coil

enwinding the magnet. The crankshaft signal wheel is one toothed disc, which originally has 60

teeth, but with two missing teeth. The signal wheel is installed on the crankshaft and rotates along

with the crankshaft. When the tip of tooth passes through the tip of crankshaft position sensor, the

signal wheel made of ferromagnetic material cuts the magnetic force line of permanent magnet in

the speed sensor to generate induced voltage within the coil as the speed signal output.

Performance:

Operating temperature: -40～150

Working gap: 0.5-1.5 mm

2. Installation position

It’s installed in the vicinity of the crankshaft.

3. Wiring Diagram

Pin46: Terminal B of crankshaft position sensor

Pin 47: Terminal A of crankshaft position sensor

Fig. 4.3.009

Crankshaft Position Sensor


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4. Diagnosis

ECU real-time monitoring of the sensor and circuit

Sensor open circuit;

Internal short-circuit of sensor;

Sensor unit short-circuit to ground

Sensor unit short-circuit to system reference voltage signal wire.

5. Trouble Solution

Check sensor circuit for normal function and incorrect connection of grounding

Connect the sensor and harness to check whether the connections of power supply, grounding wire,

and signal wire are normal.

6. Removal and installation

1）Removal

① Disconnect the harness connector of crankshaft position sensor.

Speed sensor


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188

② Unscrew fixing bolts, remove the sensor.

2） Installation

Be aware of following precaution to install with steps contrarily.

Be aware of installation gap.

Standard: 0.5 - 1.5mm

Tightening torque: 7.8 - 9 N • m

V. Camshaft phase sensor


This sensor provides crankshaft phase information to the ECU, namely differentiating the

compression top dead center and the exhaust top dead center of the crankshaft.

This sensor is manufactured by means of the Hall theory in which the Hall voltage is subject to the

varying magnetic field induction strength.

Fig. 4.3.010

Fig. 4.3.011


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189

Theory of Hall sensor: When a current IS flows

through a semi-conductor chip, one Hall voltage is

generated in the right-hand direction of the

current, of which the voltage UH is in proportion

to the magnetic field induction B (perpendicular to

the current IS) and the current IS. The Hall voltage

is subject to the varying magnetic field induction

strength B.

Performance:

Operating temperature: -40～150

Working gap: 0.5-1.5 mm


It’s installed in the vicinity of the camshaft.

3. Wiring Diagram

Pin 39: Sensor grounding

Pin 42: Sensor signal

Pin 18: 5V power supply

BBBB

IUH

Fig. 4.3.012

Camshaft position sensor


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190

4. Diagnosis

ECU real-time monitoring of the sensor and circuit

Sensor open circuit;

Internal short-circuit of sensor;

Sensor unit short-circuit to ground

Sensor unit short-circuit to system reference voltage signal wire.

5. Trouble Solution

Check sensor circuit for normal function and incorrect connection of grounding

Connect the sensor and harness to check whether the connections of power supply, grounding wire,

and signal wire are normal.


1）Removal

① Disconnect the harness connector of camshaft position sensor.

② Unscrew fixing bolts, remove the sensor.

Phase sensor

Fig. 4.3.013


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191

2） Installation

Be aware of following precaution to install with steps contrarily.

Be aware of installation gap.

Standard: 0.5 - 1.5mm

Tightening torque: 7.8 - 9 N • m

VI. Oxygen sensor


Oxygen sensor is used to provide information for judging whether the oxygen in air inhaled to the fuel

in engine cylinder is excessive or not after combustion. ECU uses this quantitative information for

defined cycle control of the fuel cycle so that the three major toxic components can be mostly converted

and purified in the three-way catalytic converter.

The sensing component is a kind of porous ceramic tube; the wall is surrounded by the engine exhaust

while the inside is put through to the atmosphere. The oxygen sensor, based on concentration difference

inside and outside, calculates indirectly the fuel injection pulse width to be transmitted to ECU for

controlling of fuel injection. Simultaneously, it detects rear oxygen sensor output data and compares

with front sensors data within the ECU to monitor the working conditions of the three-way catalyst

converter.

Oxygen sensor operating voltage fluctuates between 0.1-0.9V; in 10 seconds it may change for 5-8 times;

if it is lower, indicates that the sensor is aged and need to be replaced. The sensor can not be repaired.

Fig. 4.3.014


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192


Front (upstream) oxygen sensor is installed on the

exhaust manifold before the three-way catalyst

converter and the rear (downstream) oxygen sensor is

installed behind the three-way catalytic converter.

3. Wiring diagram

Pin 39: Downstream oxygen sensor grounding

Pin 29: Downstream oxygen sensor signal

Pin 4: Downstream oxygen sensor heating control

1#: To main relay power

Pin 39: Upstream oxygen sensor grounding

Pin 45: Upstream oxygen sensor signal

Pin 2: Upstream oxygen sensor heating control

1#: To main relay power

4. Diagnosis

ECU detects the oxygen sensor circuit and ECU internal power amplifier circuit and testing circuit. If

one of the following conditions occurs, the oxygen sensor fault indicator will be set:

Battery voltage not reliable

Intake manifold absolute pressure signal not reliable

Engine coolant temperature signal not reliable

Downstream oxygen sensor

Upstream oxygen sensor

Main relay

Main relay

Fig.4.3.015


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193

Injector drive-level fault

Oxygen sensor fault indication is set, with the fuel cycle quantitative control cut off; use the basic fuel

injection time stored in the ECU for the quantitative fuel control.

5. Diagnosis

Mainly check sensor wiring connection for short circuit, open circuit;

Sensor damages are generally caused by lead or phosphorus poisoning; so pay attention to the fuel

quality; meanwhile, excessive fuel consumption may also lead to sensor failure;

Changes of the oxygen sensors should be not less than a certain times in certain period of time.


1) Dismantlement

① Disconnect oxygen sensor harness connector.

② Remove oxygen sensor with special remover.

Attention:

Plug mounting hole of the oxygen sensor with hairless cotton yarn to keep the debris or oil &

water away from the exhaust manifold.

Visually inspect appearance of oxygen sensor.

Reddish brown: lead poisoning

Off-white: normal

Black: carbon deposition

2) Installation

Fig. 4.3.016

Fig. 4.3.017


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194

Be aware of following items to install with steps contrary to dismantlement.

Be aware of routing of oxygen sensor wire harness.


After replacement of oxygen sensor, oxygen sensor should be coated with a layer of anti-rust oil to

prevent rust which impede removal.

VII. Fuel Injector (INJ)


Fuel coming from the fuel pump is stored and distributed via the fuel rail components and provides the

fuel system with a more stable pressure environment in which the fuel supply pressure and quantity of

each cylinder will be balanced while the engine is running smoothly. Injector injects fuel as per the

signal from the ECM signal and defines fuel injection volume depending on opening time of injector

solenoid valve.


It is installed on the fuel guide rail.

3. Wiring Diagram

Fig. 4.3.018


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195

1# cylinder fuel injector 2# cylinder fuel injector 3# cylinder fuel injector

4. Inspection

Attention:

Please clean the fuel injector and analyze with special cleaning and analysis instrument for fuel

inject at certain interval..

1) Check the resistance.

Note: check with wire harness connector disconnected.

Standard resistance: 11.4-12.6Ω

2) Inspect operating time of the fuel injector with trouble diagnosis apparatus.

Standard operation time: 2.0-3.0ms at the idle speed and more during the acceleration.

3) Check the operating sound of fuel injector.

Note: Use a stethoscope to check the click sound of the fuel injector at the idling speed or use the

fingers to check the vibration situation of fuel injector.

If vibration can not be felt, check the wire harness connector, fuel injector or the control signal of fuel

injector by ECM.


Please refer to “Fuel System”.

VIII. Knock sensor

To main relay


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196

1. Description

Knock sensor is installed in the cylinder block side usually between the 2, 3-cylinder, it is helpful for

engine knock balance; the ECU uses the knock sensor output vibration frequency signal to judge

whether there is knock with ECU internal filtering. When the knock signal is detected, ECU will

gradually reduce it until the knock disappeared; and then gradually restore to the knock threshold; the

cycle is done repeatedly.


Installed aside of cylinder.

3. Inspection

1) Wiring diagram

Pin 30: Terminal A of knock sensor

Pin 31: Terminal B of knock sensor

2) Check the resistance.

Resistance: greater than 1MΩ

4. Diagnosis:

ECU monitors the knock sensor, power amplifier circuit and testing circuit. If one of the following

circumstances is detected, knock sensor fault indication will be set:

Knock sensor failure;

Knock control data processing circuit fault;

Fig. 4.3.019

Knock sensor


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197

Cylinder judging signal not reliable;

Sensor circuit failure.

After knock sensor fault flagging out the failure position, knock set control loop is Disconnect and the

advance angle of ignition stored in the ECU will be fixed to a safe angle by the software program. When

the error frequency drops below the set value, the fault indication will reset.


1） Removal

① Disconnect knock sensor harness connector.

② Unscrew knock sensor locking nut, remove the knock sensor.

Attention:

Do not drop or damage the sensor.

2) Installation

Install with reversed steps of disassembly.

Tightening torque: 16 - 24N • m

IX. Air-conditioning switch and relay

1. Description

When air conditioner is turned on, the air conditioning switch will send the battery voltage signal to the

ECM. After air conditioner turned-on signal input, ECM drives electronic throttle to increase idling

speed of engine, and correct ignition advance angle. At the same time, ECM controls air conditioning

relay to make the compressor magnetic clutch working.

2. Inspection

Fig. 4.3.020


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198

With engine idling, use fault diagnostic apparatus to check air-conditioning switch for normal working.

Air conditioning switch Checklist

Items Air conditioning switch Normal direction

Off Off Air conditioning switch

On On

Off Off (compressor clutch does not work) Air compressor

On On (compressor clutch works)

X. Canister solenoid valve

1. Description

Control air intake from the canister to the general intake piping. The adsorption amount of canister has

certain limits, if evaporation of gasoline attached to the canister is not consumed, it may emit into

ambient air resulting in pollution and increased insecurity.

Internal of canister valve is a solenoid valve structure and its opening is controlled with the digital pulse

square wave sent from the ECU. According to different engine operating conditions, canister solenoid

valve opening is also different; at big loading of the engine and idle time, canister solenoid valve is not

working in order to ensure the engine's output power.


3. Wiring diagram

A: Main relay output end

Pin 35: Canister solenoid valve control signal

4. Diagnosis

Fig. 4.3.021

Canister solenoid valve

Main relay


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199

Short circuit of sensor with ground

Short circuit of sensor with power line

Open circuit of sensor

5. Trouble Solution

Check sensor signal for short circuit, open circuit;

Check wiring harness for channeling;

Check sensor circuit for short circuit with power line;

Check canister magnet valve for blockage and normal ventilation;

Operating Temperature: -40 - 120 ;

Coil resistance: 19 - 22Ω;

Working voltage: 8 - 16V;


1） Removal

① Disconnect hose at canister solenoid valve

side.

② Disconnect the canister solenoid valve wiring

harness connector.

③ Take off the canister solenoid from the cage.

2） Installation

Be aware of following precautions to install with steps contrary to removal.

When installing, air flow direction must meet requirement, meanwhile checking the canister

solenoid valve for wearing and cracks.

During the disassembly process, avoid water, oil and other liquid entering into the valve.

XI. Ignition coil

Fig. 4.3.022

Fig. 4.3.023


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200

1. Description

Ignition coil converts the low voltage of the primary winding into the high voltage of secondary winding

and discharged at spark plug to ignite the fuel air mixture in cylinder.

This engine adopts independent ignition technology and utilizes the theory of high energy utilization by

the mutual inductance of electromagnetic coil to control the energization time and power-off moment of

the secondary coil and utilize the high voltage generated in the secondary stage of the coil to puncture

the gap of spark plug, generate strong spark, and ignite the gas mixture. Due to high air ionization

degree and low resistance during engine exhaust stroke, it only needs a low voltage to puncture the gap

of spark plug. Therefore, this system adopts grouped ignition technology, which will not waste any

energy and will save a great amount of cost.

Ignition coil operating voltage range: 6 - 16V

Secondary ignition coil resistance: 8.7 ± 0.87 KΩ

Primary charge time: 2.15ms

Minimum ignition duration: 1.0ms

Minimum ignition energy: 35mJ.


Installed at top of the cylinder head cover.

Fig. 4.3.025

Fig. 4.3.024


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3. Diagnosis

ECU does not function to diagnose ignition coil failures. Therefore, if there is any failure of ignition coil,

no DTC is set. Only by checking the ignition coil resistance can the proper working of the ignition coil

be determined; under normal circumstances, the ignition coil heats up more during working, but

overheated temperature of the ignition coil causes increaseing in ignition coil resistance, resulting in

instability of engine work, automatic flameout and other failures. But the ECU can detect the control

cable of the ignition coil. When failure of an ignition coil is detected, injector of corresponding cylinder

will be turned off.

Control cable short circuit with ground;

Control cable short circuit with power line;

Control circuit open.

4. Diagnosis

Internal short circuit, open circuit of coil;

Coil leakage, cracks in the housing;

Aging coil leading to energy shortage in ignition.


For removal and installation, please see "Ignition System."

XII. Electric Fuel Pump

1. Description

It is used to deliver the fuel to the main fuel supply pipe from the fuel tank at a certain fuel pressure and

flow, and maintain the stable fuel pressure (through the fuel pressure regulator).


It is installed inside the fuel tank

3. Wiring diagram

Pins description: the electric fuel pump has two pins, and the fuel pump casings next to the two pins are

marked with "+" and "-" signs, which represent respectively the connections to the positive (fuel pump

relay) and ground.


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4. Inspection

1) Check internal resistance of fuel pump.

Internal resistance should not be zero or infinity.

2) Check the fuel pressure

Refer to “Fuel System”.


Refer to “Fuel Pump Assembly”.

Attention:

In order to prevent accidental damage of fuel pump, please do not run the fuel pump without

fuel.

In case that the fuel pump need to be replaced, please pay attention to the cleaning of fuel tank

and pipeline and replacement of fuel filter.

Fuel pump relay

Fuel pump


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XIII. Electronic Control Module (ECM) of Engine

1. System description

The greatest characteristic in the electronic control system of the M7 engine is the adoption of

torque-based control strategy. The torque-based control strategy is mainly intended to link a great

amount of different control objectives. This is the sole method to integrate flexibly all kinds of functions

into different variants of ECU depending on the engine and vehicle models.

In the engine electronic control system, the sensors are functioned as input parts to measure all kinds of

physical signals (temperature, pressure, etc.) and convert to corresponding electric signals, the ECU is

functioned to receive the input signals from sensors, calculate and process as per preset programs,

generate corresponding control signals, and output to power drive circuits, and the power drive circuits

execute different actions by driving corresponding actuators and control the engine to run as per preset

control strategy. At the same time, the malfunction diagnosis system of ECU monitors various

components and control functions in the system. Once a malfunction is detected and confirmed, the

system will save the malfunction code and activate the “Limp home” function. Upon the detection that

the malfunction is resolved, the system will resume to normal values.

1） Functions

Torque-based system structure

Determine cylinder load quantity based on intake pressure sensor

Improve control function of gas mixture under static and dynamic conditions

λ closed-loop control

Fuel cylinder-by-cylinder sequential injection

Ignition timing (including cylinder-by-cylinder knock control)

Exhaust control function

Catalytic converter heating control

Carbon canister control

Idling control

Limp home

Anti-theft device function

Connection between torque and external system

Control over central electronic control parts

Complete a series of OBDII control functions

Used for management system of diagnosis function

etc.


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2） ECM pin definitions:

ECM pin definition list

Pin Function Pin Function

1 Reserved terminal 33 Reserved terminal

2 Heating of upstream oxygen sensor 34 Reserved terminal

3 Ignition coil 1 35 Phase terminal C of stepping motor

4 Heating of downstream oxygen sensor 36 Phase terminal D of stepping motor

5 5V grounding 37 Carbon canister electromagnetic valve

6 Reserved terminal 38 Reserved terminal

7 Ignition coil 2 39 Sensor grounding 1

8 Non-sustained power supply 40 Sensor grounding 2

9 Engine speed output 41 Engine coolant temperature sensor

10 A/C medium pressure switch 42 Phase sensor

11 Reserved terminal 43 Electric grounding 1

12 Headlamp switch 44 A/C switch

13 Reserved terminal 45 Upstream oxygen sensor

14 Reserved terminal 46 Terminal B of engine speed sensor

15 Diagnosis K-line 47 Terminal A of engine speed sensor

16 Sustained power supply 48 Power grounding 1

17 Ignition switch 49 Fuel injector 2 (3rd

cylinder)

18 5V power supply 2 50 Fuel injector 1 (1st cylinder)

19 5V power supply 1 51 Non-sustained power supply

20 Malfunction indicator lamp 52 High speed fan relay

21 Phase terminal B of stepping motor 53 Reserved terminal

22 Phase terminal A of stepping motor 54 Reserved terminal

23 SVS lamp 55 Reserved terminal

24 Fan switch 56 Reserved terminal

25 Intake temperature sensor 57 Vehicle speed signal

26 Throttle position sensor 58 Reserved terminal

27 Reserved terminal 59 Intake pressure sensor

28 Reserved terminal 60 Oil pump relay

29 Downstream oxygen sensor 61 A/C compressor relay

30 Terminal A of knock sensor 62 Low speed fan relay

31 Terminal B of knock sensor 63 Fuel injector 4 (2nd

cylinder)

32 Main relay 64 Reserved terminal

* Specific pin number is subject to harness schematic diagram (standby terminal defined as empty pin).


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Installation position is shown in the figure right.

4. Inspection

1) Read the engine trouble record with the data wire K.

2) Check whether the connecting wire of ECM for normal conditions and put the focus on the ECM

power supply and grounding line.

3) Check for normal conditions of external sensor and reliability of output signal normal connection of

its circuit.

4) Check whether the actuator is normal and whether its line is intact.

5) Finally, replace the ECM to carry out the test.


1) Dismantlement

① Turn the ignition switch to “OFF” position to dismantle the negative terminal of battery.

② Dismantle the lower part of the console referring to “console”.

③ Disconnect the wire harness connector of ECM port. Refer to “Precautions”.

④ Unscrew fixing bolts of ECM to remove the ECM.

2) Installation


For precautions about the installation, please refer to “Precautions”.

Fig. 4.3.026


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Section IV Trouble Diagnosis Procedures for Engine Control System

I. Diagnosis with DTC

1. Instruction

1) The following Repair can be carried out only after the current stable trouble has been identified,

otherwise the diagnosis will be wrong.

2) The "multi-meter" hereinafter refers to the digital multi-meter and it is not permitted to use the

analog multi-meter to check the electric control system circuits.

3) When carrying out the Repair for the vehicle with the anti-theft system, if the requirement of

replacing the ECM is included in the "Next Steps" column, it is necessary to program the ECM

after replacement.

4) If the DTC points to low voltage of a specific circuit, it indicates that the circuit is likely to have

short circuit with ground or open circuit; if the DTC points to high voltage of a specific circuit, it

indicates that the circuit is likely to have short circuit with power circuit; if the DTC points to a

circuit trouble, it indicates that the circuit is likely to have broken circuit or a variety of line

troubles.

2. Diagnosis Help

1) If the DTC can not be erased, it means the trouble is stable; in case of the sporadic trouble, it is

necessary to check whether the connector of wire harness is loosened.

2) The check has been accomplished with steps above and nothing unusual has been found.

3) Effects of the maintenance of vehicle, cylinder pressure and mechanical ignition timing etc. on the

system should not be neglected during the inspection and repairing.

4) Replace the ECM to carry out the test.

If the DTC can be cleared at this time, it means the trouble site is at ECM; if the DTC still can not

be erased at this point, then remount the original ECM and repeat the procedures again to carry out

the Repair.


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3. DTC Diagnosis

ECM pins referred to below should be subject to the actual wire harness diagrams.

Fault code: P0107 “the intake pressure sensor is short to ground”

S/N Step Check result Subsequent step

1 Connect the diagnosis device and adapter, and turn the ignition switch

to ON position. Next step

Yes To Step 5 2

Check if the intake pressure in the data flow is about 101kpa

(depending on the air pressure then).。 No Next step

Yes To Step 5 3

Unplug the connector of intake pressure sensor on the harness, and

measure if the voltage between Pins 3# and 1# of this connector is

about 5V by the multimeter. No Next step

Yes Repair or replace

the harness 4

Check if the circuits connecting Pins 40#, 19# and 59# of ECU

respectively to Pins 1#, 3# and 4# of sensor connector are short to

ground. No Next step

Yes Diagnosis help

5

Start the engine and run the engine idly. Slowly depress the

accelerator pedal and almost open the throttle completely; observe the

change of the “Intake pressure” value on the diagnosis meter, and at

this moment, the displayed value shall not change significantly; fast

depress the accelerator pedal and almost open the throttle completely,

and at this moment, the displayed value can reach above 90kpa

instantly.

No Replace the

sensor

Fault code: P0108 “the intake pressure sensor is short to power source”




Yes To Step 5 2

Check if the intake pressure in the data flow is about 101kpa

(depending on the air pressure then). No Next step

Yes To Step 5 3

Unplug the connector of intake pressure sensor on the harness, and

measure if the voltage between Pins 3# and 1# of this connector is

about 5V by the multimeter. No Next step


the harness 4

Check if the circuits connecting Pins 40#, 19# and 59# of ECU

respectively to Pins 1#, 3# and 4# of sensor connector are open or

short to power source. No Next step

Yes Diagnosis help

5

Start the engine and run the engine idly. Slowly depress the

accelerator pedal and almost open the throttle completely; observe the

change of the “Intake pressure” value on the diagnosis meter, and at

this moment, the displayed value shall not change significantly; fast

depress the accelerator pedal and almost open the throttle completely,

and at this moment, the displayed value can reach above 90kpa

instantly.

No Replace the

sensor


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Fault code: P0112 “the signal voltage of intake temperature sensor is too low”




Yes To Step 5

2

Observe if the “Intake temperature” in the data flow is equivalent to

the temperature inside the intake pipe (depending on the engine

temperature then).

Notice: if the displayed value is always -40 , the circuit may be

open. No Next step

Yes Next step

3

Unplug the connector of intake temperature sensor on the harness,

and check if the resistance between Pins 1# and 2# of sensor

corresponds to its temperature by the multimeter (refer to the relevant

section in this repair manual for the details). No Replace the

sensor

Yes To Step 5 4


and check if the voltage between Pins 1# and 2# of this connector is

about 5v by the multimeter. No Next step


the harness 5

Check if the circuits connecting Pins 40# and 25# of ECU

respectively to Pins 1# and 2# of sensor connector are open or short

to power source. No Next step

Yes Diagnosis help

6

Start the engine and run the engine idly. Observe the change of the

“Intake temperature” value on the diagnosis meter, and at this

moment, the displayed value increases along with the rising of engine

intake temperature. No Replace the

sensor

Fault code: P0113 “the signal voltage of intake temperature sensor is high”




Yes To Step 5

2

Observe if the “Intake temperature” in the data flow is equivalent to

the temperature inside the intake pipe (depending on the engine

temperature then). Notice: if the displayed value is always -40 , the

circuit may be open. No Next step

Yes Next step

3





sensor

Yes To Step 5 4





the harness 5


respectively to Pins 1# and 2# of sensor connector are short to


Yes Diagnosis help

6


“Intake temperature” value on the diagnosis meter, and at this

moment, the displayed value increases along with the rising of engine

intake temperature. No Replace the

sensor


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Fault code: P0117 “the circuit voltage of engine coolant temperature sensor is too low”




Yes To Step 6

2

Observe if the “Coolant temperature” in the data flow is equivalent to

the engine temperature (depending on the engine temperature then).


open. No Next step

Yes Next step

3

Unplug the connector of coolant temperature sensor on the harness,




sensor

Yes To Step 6 4





the harness 5


respectively to Pins 1# and 2# of sensor connector are open or short

to power source. No Next step

Yes Diagnosis help

6


“Coolant temperature” value on the diagnosis meter, and at this

moment the displayed value shall increase with the rising of engine

coolant. No Replace the

sensor

Fault code: P0118 “the circuit voltage of engine coolant temperature sensor is too high”




Yes To Step 6

2

Observe if the “Coolant temperature” in the data flow is equivalent to

the engine temperature (depending on the engine temperature then).


open. No Next step

Yes Next step

3





sensor

Yes To Step 6 4





the harness 5


respectively to Pins 1# and 2# of sensor connector are short to


Yes Diagnosis help

6


“Coolant temperature” value on the diagnosis meter, and at this

moment the displayed value shall increase with the rising of engine

coolant. No Replace the

sensor


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Fault code: P0122 “the circuit voltage of throttle position sensor is at the extremely low limit”




Yes Next step 2

Observe if the value of “Throttle opening” is between 4% and 10%

(depending on the bus model). No To Step 5

Yes Next step

3

Slowly depress the accelerator pedal to fully open the throttle, and

observe if the value of “Throttle opening” in the data flow increases

to 85-95% along with the increase of throttle opening (depending on

the bus model). No To Step 5

Yes Replace the

sensor 4 Repeat Step 3 and observe if the value of “Throttle opening” in the

data flow springs during change. No Next step


the harness 5

Unplug the connector of throttle position sensor on the harness, and

check if the circuits connecting Pins 39#, 18# and 26# of ECU

respectively to Pins 1#, 2# and 3# of sensor connector are short to


Yes Replace the

sensor 6 Check if the voltage between Pins 1# and 2# of this connector is

about 5V by the multimeter. No Diagnosis help

Fault code: P0123 “the circuit voltage of throttle position sensor is at the extremely high limit”




Yes Next step 2

Observe if the value of “Throttle opening” is between 4% and 10%

(depending on the bus model). No To Step 5

Yes Next step

3

Slowly depress the accelerator pedal to fully open the throttle, and

observe if the value of “Throttle opening” in the data flow increases

to 85-95% along with the increase of throttle opening (depending on

the bus model). No To Step 5

Yes Replace the

sensor 4 Repeat Step 3 and observe if the value of “Throttle opening” in the

data flow springs during change. No Next step


the harness 5

Unplug the connector of throttle position sensor on the harness, and

check if the circuits connecting Pins 39#, 18# and 26# of ECU

respectively to Pins 1#, 2# and 3# of sensor connector are open or

short to power source. No Next step

Yes Replace the

sensor 6 Check if the voltage between Pins 1# and 2# of this connector is

about 5V by the multimeter. No Diagnosis help


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Fault code: P0130 “the signal of upstream oxygen sensor is unreasonable”




Yes Diagnosis help

2

Start the engine and run the engine idly till the coolant temperature

reaches to the normal value. Observe the change of the value of

“Oxygen sensor voltage” on the diagnosis meter, and at this moment,

the displayed value shall change fast between 100mV and 900mV. No Next step


the harness 3


respectively to Pin 3# (relative to gray connecting wire of oxygen

sensor) and Pin 4# (relative to black connecting wire of oxygen

sensor) of sensor connector are short to ground. No Next step

Yes

Make check and

repair according

to diagnosis

results. 4

A. Check if the intake system has serious leakage.

B. Check if the fuel injector is blocked.

C. Check if the spark plug clearance is too big.

D. Check if the resistance of live wire branch is too high.

E. Check if the intake valve guide is worn.

Etc. No Diagnosis help

Fault code: P0131 “the circuit voltage of upstream oxygen sensor signal is too low”




Yes Diagnosis help

2






the harness 3




sensor) of sensor connector are short to power source. No Diagnosis help

Fault code: P0132 “the circuit voltage of upstream oxygen sensor signal is too high”




Yes Diagnosis help

2






the harness 3




sensor) of sensor connector are short to power source. No Diagnosis help


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Fault code: P0134 “the upstream oxygen sensor signal is in trouble”




Yes Diagnosis help

2






the harness 3




sensor) of sensor connector are open. No Diagnosis help

Fault code: P0171 “the closed loop control self leaning of off-line air/fuel ratio test is too infrequent”

(Note: the following diagnosis procedures are applicable to the case that the fault codes of intake

pressure sensor, canister control valve, oxygen sensor and so on do not occur together; if the relevant

fault codes exist at the same moment, please firstly solve other faults and then make check and repair

according to the following procedure.)




Yes Next step

2


reaches to the normal value.

Under all the work conditions, observe the change of the value of


check if the displayed value remains at 100mV or so for a long time

under a certain condition.

No Diagnosis help

Yes Next step

3

Connect the fuel pressure meter to the fuel system inlet pipe, and

observe if the fuel pressure remains at 350kPa or so under all the

work conditions. No Check and repair

the fuel system


the harness 4




sensor) of sensor connector are short to ground. No Next step

Yes

Make check and

repair according

to diagnosis

results. 5

A. Check if the intake system has serious leakage;


C. Check if the spark plug clearance is too big.

D. Check if the resistance of live wire branch is too high.

E. Check if the intake valve guide is worn.


Fault code: P0172 “the closed loop control self leaning of off-line air/fuel ratio test is too frequent”

(Note: the following diagnosis procedures are applicable to the case that the fault codes of intake

pressure sensor, canister control valve, oxygen sensor and so on do not occur together; if the relevant

fault codes exist at the same moment, please firstly solve other faults and then make check and repair

according to the following procedure.)


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Yes Next step

2


reaches to the normal value.

Under all the work conditions, observe the change of the value of


check if the displayed value remains at 900mV or so for a long time

under a certain condition.

No Diagnosis help

Yes Next step

3

Connect the fuel pressure meter to the fuel system inlet pipe, and

observe if the fuel pressure remains at 350kPa or so under all the

work conditions. No Check and repair

the fuel system


the harness 4




sensor) of sensor connector are short to power source. No Next step

Yes

Make check and

repair according

to diagnosis

results. 5

A. Check if the fuel injector drips fuel.

B. Check if the exhaust pipe has leakage.

C. Check if the ignition timing is incorrect.


Fault code: P0201 “the control circuit of fuel injector of Cylinder 1# is open”




Yes To Step 4

2

Unplug the connector of the fuel injector of Cylinder 1# on the

harness, and check if the voltage between Pin 1# of this connector

and the negative pole of power source is about 12V by the

multimeter. No Next step


the harness 3 Check if the circuit between Pin 1# of the fuel injector connector of

Cylinder 1# and the main relay is open or short to ground. No Next step

Yes Next step

4 Check if the resistance between Pins 1# and 2# of the fuel injector of

Cylinder 1# at 20 is between 11Ω and 13Ω by the multimeter. No Replace the fuel

injector

Yes Diagnosis help 5

Check if the voltage between Pin 2# of the fuel injector of Cylinder

1# and the negative pole of power source is about 3.7V by the



the harness 6

Check if the circuit between Pin 2# of the fuel injector connector of

Cylinder 1# and Pin 50 of ECU is open or short to power source or

ground. No Diagnosis help


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Yes To Step 4

2








Yes Next step


Cylinder 2# at 20 is between 11Ω and 13Ω by the multimeter. No Replace the fuel

injector






the harness 6








Yes To Step 4

2








Yes Next step


Cylinder 3# at 20 is between 11Ω and 13Ω by the mul timeter. No Replace the fuel

injector






the harness 6





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Fault code: P0327 “the circuit voltage of knocking sensor signal is too low”



to OFF position. Next step

Yes Next step

2

Unplug the knocking sensor connector on the harness, and check if

the resistance between Pins 1# and 2# of knocking sensor is higher

than 1MΩ by the multimeter. No Replace the

sensor


the harness 3

Check if the circuits connecting to Pins 1# and 2# of knocking sensor

connector to Pins 30# and 31# of ECU are open or short to power

source or ground. No Next step

Yes Diagnosis help

4

According to the specifications, replace the knocking sensor, test the

car and make engine rotation speed higher than 2200rpm. Check if

the fault code P0327 appears again. No

Check if it is a

sporadic fault

Fault code: P0328 “the circuit voltage of knocking sensor signal is too high”




Yes Next step

2

Unplug the knocking sensor connector on the harness, and check if

the resistance between Pins 1# and 2# of knocking sensor is higher

than 1MΩ by the multimeter. No Replace the

sensor


the harness 3

Check if the circuits connecting to Pins 1# and 2# of knocking sensor

connector to Pins 30# and 31# of ECU are open or short to power

source or ground. No Next step

Yes Diagnosis help

4

According to the specifications, replace the knocking sensor, test the

car and make engine rotation speed higher than 2200rpm. Check if

the fault code P0328 appears again. No

Check if it is a

sporadic fault

Fault code: P0340 “the mounting position of phase sensor is incorrect”




Yes To Step 4

2

Unplug the phase sensor connector on the harness, and check if the

voltage between Pins 3# and 1# of this connector is about 12V by the



the harness 3

Check if the circuit connecting Pin 3# of phase sensor to Pin 87# of

main relay is open or short to ground.

Check if Pin 1# of phase sensor is grounded improperly. No Next step


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217


Yes To Step 6 4

Check if the voltage between Pin 2# of phase sensor and the negative

pole of power source is about 9.9V. No Next step


the harness 5 Check if the circuit connecting to Pin 2# of phase sensor connector to

Pin 42# of ECU is open or short to power source or ground. No Next step

Yes Diagnosis help

6 Check if the signal panel of camshaft is good. No

Replace the

signal panel

Fault code: P0341 “the contact of phase sensor is not good”




Yes To Step 4

2





the harness 3




Yes To Step 6 4






Yes Diagnosis help


Replace the

signal panel

Fault code: P0342 “the phase sensor is short to ground”




Yes To Step 4

2





the harness 3





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218


Yes To Step 6 4






Yes Diagnosis help


Replace the

signal panel

Fault code: P0343 “the phase sensor is short to power source”




Yes To Step 4

2





the harness 3




Yes To Step 6 4






Yes Diagnosis help


Replace the

signal panel

Fault code: P0444 “the control circuit of canister control valve is open”




Yes To Step 4 2

Unplug the connector of canister control valve on the harness, and

check if the voltage between Pin 1# of this connector and the negative

pole of power source is about 12V by the multimeter. No Next step


the harness 3 Check if the circuit of power supply side of canister control valve is

open or short to ground. No To Step 2

4 Check if the resistance between Pins 1# and 2# of the canister control Yes Next step


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219


valve at 20 is between 22Ω and 30Ω by the multimeter. No

Replace the

control valve


Check if the voltage between Pin 1# of the canister control valve

connector and the negative pole of power source is about 3.7V by the



the harness 6 Check if the circuit connecting Pin 2# of canister control valve

connector to Pin 37# of ECU is open. No Diagnosis help

Fault code: P0458 “the voltage of control circuit of canister control valve is too low”




Yes To Step 4 2







Yes Next step

4 Check if the resistance between Pins 1# and 2# of the canister control

valve at 20 is between 22Ω and 30Ω by the multimeter. No Replace the

control valve







connector to Pin 37# of ECU is short to ground. No Diagnosis help

Fault code: P0459 “the voltage of control circuit of canister control valve is too high”




Yes To Step 4 2







Yes Next step

4 Check if the resistance between Pins 1# and 2# of the canister control

valve at 20 is between 22Ω and 30Ω by the multimeter. No Replace the

control valve






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220




connector to Pin 37# of ECU is short to power source. No Diagnosis help

Fault code: P0480 “the control circuit of cooling fan relay is open (low speed)”




Yes To Step 4

2

Unplug the A/C condenser cooling fan relay, turn the ignition key to

“ON” position, and check if the voltage between the relay power

supply side (namely Pins 30# and 87# of relay) and the negative pole

of power source is about 12V. No Next step


the harness 3 Check if the circuit of power supply side of A/C condenser cooling

fan relay is open or short to ground. No To Step 2

Yes Replace the relay

4

Check if the voltage between the control side of A/C condenser

cooling fan relay (namely Pin 86# of relay) and the negative pole of

power source is about 3.7V by the multimeter. No Next step


the harness 5 Check if the circuit connecting to Pin 86# of relay control side to Pin

62# of ECU is open or short to power source or ground. No Diagnosis help

Fault code: P0481 “the control circuit of cooling fan relay is open (high speed)”




Yes To Step 4

2

Unplug the A/C condenser cooling fan relay, turn the ignition key to

“ON” position, and check if the voltage between the relay power

supply side (namely Pins 30# and 87# of relay) and the negative pole

of power source is about 12V. No Next step


the harness 3 Check if the circuit of power supply side of A/C condenser cooling

fan relay is open or short to ground. No To Step 2

Yes Replace the relay

4

Check if the voltage between the control side of A/C condenser

cooling fan relay (namely Pin 86# of relay) and the negative pole of

power source is about 3.7V. No Next step


the harness 5 Check if the circuit connecting to Pin 86# of relay control side to Pin

52# of ECU is open or short to power source or ground. No Diagnosis help


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221

Fault code: P0501 “the vehicle speed signal is unreasonable”




Yes Check and repair

ABS system 2 For the car with ABS system, please check if the ABS system has any

fault code. No Next step

Yes Next step

3 Check if the finger of speedometer operates normally. No

Check and repair

the instrument

circuit

Yes Next step

4 Check if the vehicle speed sensor operates normally. No

Replace the

vehicle speed

sensor


the harness 4 Check if the circuit connecting to vehicle speed sensor signal wire to

Pin 57# of ECU is open or short to power source or ground. No Diagnosis help

Fault code: P0506 “the idle speed is the lower than the target idle speed”




Yes Next step

2 Check if the adjusting screw, cable and condition of throttle are good. No

Do the necessary

repair and

maintenance

Yes Next step

3 Check if the working condition of idle regulator is good. No

Do the necessary

repair and

maintenance

Yes Do the necessary

check and repair

4

A. Check if the pressure of fuel supply system is too low.


C. Check if the system exhaust line is blocked. No Diagnosis help

Fault code: P0507 “the idle speed is the higher than the target idle speed”




Yes Next step

2 Check if the adjusting screw, cable and condition of throttle are good. No

Do the necessary

repair and

maintenance


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222

Yes Next step

3 Check if the working condition of idle regulator is good. No

Do the necessary

repair and

maintenance

Yes Do the necessary

check and repair 4

A. Check if the system leaks air

B. Check if the fuel injector drips fuel.

C. Check if the pressure of fuel supply system is too high. No Diagnosis help

Fault code: P0508 “the drive pin of stepping motor is short to ground”




Yes Next step

2

Unplug the idle regulator connector, and check if the resistances

between Pins A and D and Pins B and C of stepping motor at 20

are 53±5.3Ω. No

Replace the

stepping motor


the harness 3

Check if the circuits connecting Pins A, B, C and D of stepping motor

connector respectively to Pins 22#, 21#, 35# and 36# of ECU are

short to ground. No Diagnosis help

Fault code: P0509 “the drive pin of stepping motor is short to power source”




Yes Next step

2

Unplug the idle regulator connector, and check if the resistances

between Pins A and D and Pins B and C of stepping motor at 20

are 53±5.3Ω by the multimeter. No

Replace the

stepping motor


the harness 3



short to power source. No Diagnosis help

Fault code: P0511 “the drive pin of stepping motor is in open circuit”




Yes Next step

2

Unplug the stepping motor connector, and check if the resistances

between Pins A and D and Pins B and C of idle regulator at 20 are

53±5.3Ω by the multimeter. No

Replace the

stepping motor


the harness 3



open. No Diagnosis help


of Engine

223

Fault code: P0560 “the voltage signal of system battery is unreasonable”




Yes Next step

2 Check if the battery voltage is about 12V by the multimeter. No

Replace the

battery


the harness 3 Check if the circuits connecting Pin 8# and 51# of ECU respectively

to Pin 87# of main relay are open or short to ground. No Next step

Yes Next step

4 Start the engine, and check if the charging voltage of generator is

always between 9V and 16V within different rotation speed ranges. No Replace the

generator

Yes Diagnosis help

5 Check if the grounding point of engine harness is good. No

Repair or replace

the harness

Fault code: P0562 “the voltage of system battery is too low”




Yes Next step


Replace the

battery


the harness 3 Check if the resistances of circuits connecting Pins 8# and 51# of

ECU to Pin 87# of main relay are too high. No Next step

Yes Next step

4 Start the engine, and check if the charging voltage of generator is

always between 9V and 16V within different rotation speed ranges. No Replace the

generator

Yes Diagnosis help


Repair or replace

the harness

Fault code: P0563 “the voltage of system battery is too high”




Yes Next step


Replace the

battery

3 Start the engine, and check if the charging voltage of generator is Yes Next step


of Engine

224


always between 9V and 16V within different rotation speed ranges. No

Replace the

generator

Yes Diagnosis help


Repair or replace

the harness

Fault code: P0602 “the programming of electronic control unit is in trouble”




Yes Next step

2 Eliminate the fault code and reconfirm if this fault is a steady fault. No

The system is

normal.

3 Replace ECU. End

Fault code: P0645 “the control circuit of A/C compressor relay is open”




Yes To Step 4

2

Unplug the A/C compressor relay, turn the ignition key to “ON”

position, and check if the voltage between the relay power supply

side (namely Pins 87# and 85# of relay) and the negative pole of

power source is about 12V. No Next step


the harness 3 Check if the circuit of relay power supply side is open or short to

ground. No To Step 2

Yes Replace the relay 4

Check if the voltage between the control side of A/C compressor

relay (namely Pin 86# of relay) and the negative pole of power source

is about 3.7V. No Next step


the harness 5 Check if the circuit connecting control side of A/C compressor relay

(namely Pin 86# of relay) to Pin 61# of ECU is open. No Diagnosis help

Fault code: P0646 “the control circuit of A/C compressor relay is short to ground”




Yes To Step 4

2





3 Check if the circuit of relay power supply side is open or short to

ground. Yes

Repair or replace

the harness


of Engine

225


No To Step 2




is about 3.7V by multimeter by the multimeter. No Next step



(namely Pin 86# of relay) to Pin 61# of ECU is short to ground. No Next step

Yes Diagnosis help

6 Check if the electromagnetic clutch of A/C compressor operates

normally. No

Repair or replace

the

electromagnetic

clutch

Fault code: P0647 “the control circuit of A/C compressor relay is short to power source”




Yes To Step 4

2






the harness 3 Check if the circuit of relay power supply side is open or short to

ground. No To Step 2




is about 3.7V by multimeter. No Next step



(namely Pin 86# of relay) to Pin 61# of ECU is short to power source. No Next step

Yes Diagnosis help

6 Check if the electromagnetic clutch of A/C compressor operates

normally. No

Repair or replace

the

electromagnetic

clutch

Fault code: P1651 “the control circuit of engine malfunction lamp (SVS) is in trouble”




Yes Next step

2 Test the action of engine malfunction lamp by the “Actuator action

test” of diagnosis device, and observe if it is always off or on. No

The system is

normal.


of Engine

226



the harness 3 Check if the circuit of power supply side of engine malfunction lamp

is open or short to ground. No Next step


the harness 4

Check if the circuit connecting pin of engine malfunction lamp

control side to Pin 23# of ECU is open or short to power source or


Yes Diagnosis help 5 Check if the bulb of engine malfunction lamp operates normally.

No Replace the bulb

II. Diagnosis by Trouble Phenomena

1. Instruction

Before carrying out the trouble diagnosis steps with the engine trouble phenomenon, it is necessary to

firstly conduct the preliminary check:

1) Confirm that the malfunction indicator lamp of engine operates normally.

2) Check with trouble diagnoses apparatus to confirm that there is no trouble information record.

3) Confirm existence of the trouble complain from owner and the conditions about the occurrence of

the trouble.

And then check the appearance:

1) Check fuel pipes for leakage.

2) Check vacuum pipes for breakage or kink and proper connection.

3) Check intake pipes for blockage, leakage, flatness or damage.

4) Check high-voltage wire of ignition system for broken, aging, verify correct ignition sequence.

5) Check grounding position of wire harness for clean and firm.

6) Check the connector of each sensor and actuator for the looseness or poor contact.

Attention: If any of above-mentioned phenomena exists, firstly conduct maintenance operation

against it; otherwise the following trouble diagnosis and maintenance will be affected.

2. Diagnosis Help

1) Confirm that there is no trouble record related to engine.

2) Confirm the existence of the trouble complained by the owner.

3) The check has been done with steps above, and there is nothing unusual found.

4) It is not permitted to neglect the effects of the maintenance of vehicle, cylinder pressure,

mechanical ignition timing and fuel etc. on the system during the Repair process.

5) Replace the ECM to test.

If the trouble phenomenon can be cleared at this time, it means the trouble site is at ECM; if the trouble


of Engine

227

phenomenon still exists at this point, reinstall the original ECM and repeat the procedures again to carry

out the Repair.

Trouble phenomenon 1: during the start-up, the engine does not run or runs slowly

General trouble position:

1. Battery; 2. Starter; 3.Wire harness or ignition switch; 4.Mechanical part of engine

General diagnosis procedure:

No. Operating Steps Detection Results Subsequent Steps

Yes Next step

1

Check the voltage between the two terminals of battery with

multi-meter to see whether it is about 8-12V during starting

of engine. No Replace battery

Yes Next step

2 With ignition switch at the starting position, check voltage of

starter negative terminal to verify that it is above 8V. No

Repair or replace

wire harness

Yes Repair or replace the

starter 3 Dismantle the starter to check its operating state. Mainly

check for sticking due to open circuit or poor lubrication.

No Next step

Yes

Change with

lubricating oil of

proper grade 4

If the trouble only present in winter, then check whether too

large resistance of starter is caused by improper selection of

the lubricating oil for engine or the gearbox oil.

No Next step

Yes

Remove large

internal resistance of

engine 5

Check engine for too large internal mechanical resistance; if

it is a case, the failure of rotation or the slow rotation of

starter may occur.

No Repeat above steps


of Engine

228

Trouble phenomenon 2: Engine start to run but can not be started successfully during the

start-up


1. No fuel in the fuel tank; 2. Fuel injection pump; 3.Crankshaft position sensor; 4.Ignition coil;

5.Mechanical part of engine


No. Operating Steps Detection

Results Subsequent Steps

Yes Next step

1

Connect the fuel pressure gauge (the access point is at the front

end of the induction manifold of the fuel distribution pipe

assembly) to the engine, and start the engine to determine

whether the readings of fuel pressure gauge when idling is at

about 260kPa; disconnect vacuum hose of pressure regulator

and observe whether fuel pressure is about 300kPa.

No Repair the fuel supply

system

Yes Next step

2

Connect the electric control system diagnosis apparatus to the

engine to observe the data of "rotating speed of engine" and

start the engine to observe whether there is speed signal output. No Repair crankshaft

position sensor circuit

Yes Next step

3

Pull out the high-voltage wire of one of the cylinders and

connect the spark plug to make the spark plug electrodes

around 5mm away from the engine body, and start the engine to

check whether there is blue and white high-voltage spark.

No Repaire ignition system

Yes Eliminate mechanical

trouble of engine 4 Check the pressure of all the cylinders and observe whether the

pressure of engine cylinders is insufficient.

No Next step


Turn on the ignition switch and check whether the power

supply and earthing are normal. No Repair related circuit


of Engine

229

Trouble phenomenon 3: Difficulty in warm start


1. Poor quality of fuel; 2.Fuel injection pump; 3.Coolant temperature sensor; 4.Ignition coil




Yes Next step

1

Connect the fuel pressure gauge (the access point is at the front end

of the induction manifold of the fuel distribution pipe assembly) to

the engine and start the engine to check whether the reading of fuel

pressure gauge at idle condition is at about 260kPa. Disconnect

vacuum hose on pressure regulator and observe whether fuel

pressure is about 300kPa.

No Repair fuel supply

system

Yes Next step

2

Pull out the high-voltage wire of one of the cylinders and connect

the spark plug to make the spark plug electrodes about 5mm away

from the engine body, and start the engine to check whether there is

the blue and white high-voltage spark.

No Repair ignition system

Yes Repair circuit or

replace the sensor

3

Pull out connector of coolant temperature sensor and start the

engine to observe whether the engine is successfully started at this

time. (Alternatively, connect a 300 ohm resistance in series at the

connector of coolant temperature sensor to observe whether the

engine is successfully started at this time.)

No Next step

Yes Repair or replace 4

Check the vacuum pipe of fuel pressure regulator for the shedding

or air leakage. No Next step

Yes Change fuel 5

Check fuel conditions and observe whether the trouble phenomenon

occurs just after adding fuel. No Next step


Turn on the ignition switch and check whether the power supply

and earthing are normal. No Repair related circuit


of Engine

230

Trouble phenomenon 4: Difficulty in cold start


1. Poor quality of fuel; 2. Fuel injection pump; 3.Coolant temperature sensor; 4.Fuel injector;

5.Ignition coil; 6.Air throttle body and idle bypass air passage; 7.Mechanical part of engine



Yes Next step

1

Connect the fuel pressure gauge (the access point is at the

front end of the induction manifold of the fuel distribution

pipe assembly) to the engine and start the engine to check

whether the reading of fuel pressure gauge at idle condition

is at about 260kPa. Disconnect vacuum hose on pressure

regulator and observe whether fuel pressure is about 300kPa.


system

Yes Next step

2


connect the spark plug to make the spark plug electrodes

about 5mm away from the engine body, and start the engine

to check whether there is the blue and white high-voltage

spark.

No Repair the ignition

system


replace the sensor

3

Pull out the connector of coolant temperature sensor and

start the engine to observe whether the engine is successfully

started at this time. (Alternatively, connect a 2500 ohm

resistance in series at the connector of coolant temperature

sensor to observe whether the engine is successfully started

at this time.)

No Next step

Yes Wash the air throttle

and idle air passage 4 Gently step down the accelerator pedal to observe whether it

is easy to start. No Next step

Yes Failure of

Replacement 5

Dismantle the fuel injector and check whether there is

leakage or blockage in the fuel injector with the cleaning

analyzer special for fuel injector. No Next step

Yes Change fuel 6

Check the fuel conditions and observe whether the trouble

phenomenon occurs just after adding the fuel. No Next step

Yes

Eliminate the

mechanical trouble of

engine 7

Check the pressure states of all the cylinders of engine and

observe whether the pressure of engine cylinder is

insufficient. No Next step





of Engine

231

Trouble phenomenon 5: Engine speed is normal, but it is difficult to start all the time


1. Poor quality of fuel; 2. Fuel injection pump; 3.Coolant temperature sensor; 4.Fuel injector;

5.Ignition coil; 6.Throttle body and idle bypass air passage; 7.Intake passage; 8.Ignition timing;

9.Spark plug; 10.Mechanical part of engine



Yes Repair air intake

system 1 Check air filter for blockage and intake passage for leakage.

No Next step

Yes Next step

2

Connect the fuel pressure gauge (the access point is at the front

end of the induction manifold of the fuel distribution pipe

assembly) to the engine and start the engine to check whether the

reading of fuel pressure gauge at idle condition is at about

260kPa. Disconnect vacuum hose on pressure regulator and

observe whether fuel pressure is about 300kPa.


system

Yes Next step

3

Pull out the high-voltage wire of one of the cylinders and connect

the spark plug to keep the spark plug electrodes about 5mm away

from the engine body, then start the engine to check whether there

is the blue and white high-voltage spark. No

Repair the ignition

system

Yes Next step 4

Check the spark plug of each cylinder to observe whether model

and gap are in compliance with the specification. No Adjust or replace

Yes Repair the lien or

replace the sensor 5

Pull out the connector of coolant temperature sensor and start the

engine to observe whether the engine is successfully started at this

time. No Next step

Yes Wash throttle and

idling air passage 6 Gently step down the throttle to observe whether it is easy to start.

No Next step

Yes Failure of

Replacement 7

Dismantle the fuel injector and check whether there is leakage or

blockage in the fuel injector with cleaning analyzer special for

fuel injector. No Next step

Yes Change fuel 8

Check fuel condition and observe whether the trouble


Yes

Eliminate the


engine 9

Check pressure of all the cylinders and observe whether the

pressure of engine cylinder is insufficient.

No Next step

Yes Next step

10 Check whether the ignition sequence of engine and ignition

timing is in line with the specification. No

Repair the ignition

timing





of Engine

232

Trouble phenomenon 6: Normal start-up but unstable idling at any time


1. Poor quality of fuel; 2.Fuel injector ; 3.Spark plug; 4.Throttle body and idle bypass air passage;

5.Intake passage; 6.Idle adjustor (step motor ); 7.Ignition timing; 8.Spark plug; 9.Mechanical part

of engine.




Yes Repair the intake

system 1 Check air filter for blockage and intake passage for leakage.

No Next step

Yes Wash or replace 2 Check idle adjustor for sticking.

No Next step

Yes Next step 3

Check the spark plug of each cylinder to observe whether its model


Yes Wash 4

Check air throttle body and idle bypass air passage for carbon

deposit. No Next step

Yes Failure of

Replacement 5

Dismantle the fuel injector and use the cleaning analyzer special for

fuel injector to check whether there is leakage, blockage or too poor

flow in the fuel injector. No Next step

Yes Change fuel 6

Check fuel condition and observe whether the trouble phenomenon

occurs just after adding the fuel. No Next step

Yes

Eliminate the


engine 7


pressure difference of each engine cylinders is large.

No Next step

Yes Next step 8

Check whether the ignition sequence of engine and ignition timing

is in compliance with specification. No Repair ignition timing





of Engine

233

Trouble phenomenon 7: Normal start-up but unstable idling during the warming-up


1. Poor quality of fuel; 2. Coolant temperature sensor; 3.Spark plug; 4.Throttle body and idle bypass

air passage; 5.Intake passage; 6.Idle adjustor; 7.Mechanical part of engine.





system 1 Check air filter for blockage and air intake passage for leakage.

No Next step

Yes Next step 2

Check the spark plug of each cylinder to observe whether its model


Yes Wash related

components 3 Dismantle the idle adjustor to check whether there is carbon deposit

in the air throttle body, idle adjustor or idle bypass air passage.

No Next step


replace sensor 4


engine to observe whether the idle speed of engine is unstable

during warming-up. No Next step

Yes Failure of

Replacement 5

Dismantle the fuel injector and check whether there is leakage,

blockage or too poor flow in the fuel injector with cleaning analyzer

special for fuel injector. No Next step

Yes Change fuel 6

Check fuel condition and observe whether the trouble phenomenon

occurs just after adding the fuel. No Next step

Yes

Eliminate the


engine 7


pressure difference of each engine cylinders is large.

No Next step





of Engine

234

Trouble phenomenon 8: Normal start-up but unstable idle speed after warmed-up


1. Poor quality of fuel; 2. Coolant temperature sensor; 3.Spark plug; 4.Air throttle body and idle

bypass air passage; 5.Intake passage; 6.Idle adjustor; 7.Mechanical part of engine.




Yes Repair the intake system 1

Check air filter for blockage and air intake passage for

leakage. No Next step

Yes Next step

2

Check spark plug of each cylinder to observe whether

its model and gap are in compliance with the

specification. No Adjust or replace

Yes Wash related components

3

Dismantle the idle adjustor to check whether there is

carbon deposit in the air throttle body, idle adjustor and

idle bypass air passage. No Next step

Yes Repair circuit or replace

sensor(s) 4

Pull out the connector of coolant temperature sensor

and start the engine to observe whether the idle speed of

engine is unstable during warm-up process. No Next step

Yes Failure of replacement

5


leakage, blockage or too poor flow in the fuel injector

with cleaning analyzer special for fuel injector. No Next step

Yes Change fuel 6



Yes Eliminate mechanical trouble

of engine 7 Check pressure of all the cylinders and observe whether

the pressure difference of each engine cylinders is large.

No Next step


Turn on the ignition switch and check whether the

power supply and earthing are normal. No Repair related circuit


of Engine

235

Trouble phenomenon 9: Normal start-up but unstable idling speed or flameout with partially load

(for example, when the air conditioner is on)


1. Air conditioning system; 2. Idle adjustor; 3.Fuel injector




Yes Wash related

components 1 Dismantle the idle adjustor to check whether there is carbon deposit

in the air throttle body, idle adjustor and idle bypass air passage.

No Next step

Yes To step 4

2

Observe whether power output of engine is increased air

conditioner operation, namely, use the electric control system

diagnosis apparatus to observe the changes of ignition advance

angle, fuel injector pulse width and intake volume. No Next step

Yes Next step

3

Connect the adapter of electric control system and disconnect the

connecting wire of the pin #75 of electronic control module to

check whether there is high level signal at the wire harness end with

AC turned on. No

Repair air

conditioning system

Yes Next step 4

Inspect pressure of air conditioning system, electromagnetic clutch

of compressor and the compressor pump of air conditioner. No Repair AC system


5

Dismantle the fuel injector and check whether there is leakage,

blockage or too poor flow in the fuel injector with cleaning analyzer

special for fuel injector. No Next step





of Engine

236

Trouble phenomenon 10: Normal start-up but too high idling speed


1. Throttle body and idle bypass air passage; 2.Vacuum pipe; 3.Idle adjustor; 4.Coolant temperature

sensor; 5.Ignition timing




Yes Adjust 1 Check throttle cable for catching or overtension..

No Next step

Yes Repair intake system

2 Check air intake system and vacuum pipeline or leakage.

No Next step

Yes Wash related

components 3

Dismantle the idle adjustor to check whether there is carbon deposit

in the air throttle body, idle adjustor and idle bypass air passage.

No Next step


replace sensor 4


engine to observe whether the idle speed of engine is too high at

this time. No Next step

Yes Next step

5 Check whether the ignition timing of engine is in compliance with

the specification.

No Repair ignition timing

Yes Diagnosis help

6 Turn on the ignition switch and check whether the power supply

and earthing are normal.

No Repair related circuit


of Engine

237

Trouble phenomenon 11: Engine speed fails to increase or flameout occurs during acceleration


1. Poor quality of fuel; 2. Intake pressure sensor and air throttle position sensor; 3.Spark plug; 4.

Throttle body and idle bypass air passage; 5.Intake passage; 6.Idle adjustor; 7.Fuel injector;

8.Ignition timing; 9.Exhaust pipe.



Yes Repair intake system 1 Check air filter for blockage.

No Next step

Yes Next step

2




whether the reading of fuel pressure gauge when idling is at

about 260kPa; disconnect vacuum hose from pressure

regulator to see whether fuel pressure is about 200kPa.


system

Yes Next step 3

Check spark plug of each cylinder to observe whether its

model and gap are in compliance with the specification. No Adjust or replace

Yes Wash related

components 4

Dismantle the idle adjustor to check whether there is carbon

deposit in the air throttle body, idle adjustor and idle bypass

air passage. No Next step

Yes Next step

5 Check whether the intake pressure sensor, air throttle

position sensor and their circuits are normal. No

Repair circuit or

replace sensor(s)

Yes Failure of replacement 6


leakage or blockage in the fuel injector with cleaning


Yes Change fuel 7



Yes Next step 8

Check whether the ignition sequence of engine and ignition

timing is in compliance with specification. No Repair ignition timing

Yes Next step

9 Check whether the operation of the exhaust pipe is smooth. No

Repair or replace the

exhaust pipe





of Engine

238

Trouble phenomenon 12: Slow response of acceleration


1. Poor quality of fuel; 2. Intake pressure sensor and air throttle position sensor; 3.Spark plug;

4 .Throttle body and idle bypass air passage; 5.Intake passage; 6.Idle adjustor; 7.Fuel injector;

8.Ignition timing; 9. Exhaust pipe




system 1 Check air filter for blockage.

No Next step

Yes Next step

2





about 260kPa. disconnect vacuum hose from pressure



system

Yes Next step 3

Check the spark plug of each cylinder to observe whether its

model and gap are in compliance with the specification. No Adjust or replace

Yes Wash related

components 4




Yes Next step

5 Check whether the intake pressure sensor, air throttle position

sensor and its circuit are normal. No

Repair circuit or

replace sensor


6


leakage or blockage in the fuel injector with cleaning


Yes Change fuel 7



Yes Next step 8


timing is in line with the specification. No Repair ignition timing

9 Check whether the operation of the exhaust pipe is smooth. No Repair or replace the

exhaust pipe





of Engine

239

Trouble phenomenon 13: Powerlessness and poor performance during acceleration


1. Poor quality of fuel; 2.Intake pressure sensor and air throttle position sensor; 3.Spark plug;

4.Ignition coil; 5. Throttle body and idle bypass air passage; 6.Intake passage; 7.Idle adjustor;

8.Fuel injector; 9.Ignition timing ; 10.Exhaust pipe.



Yes Repair 1

Check whether there are such troubles as the clutch slipping,

low tire pressure, braking drag, wrong size of tire and

incorrect alignment of four wheels etc. No Next step

Yes Repair air intake system 2 Check air filter for blockage.

No Next step

Yes Next step

3





about 260kPa. Disconnect vacuum hose from pressure


No Repair fuel supply system

Yes Next step

4


connect the spark plug to keep the spark plug electrodes about

5mm away from the engine body, and start the engine to

check whether the strength of high-voltage spark.

No

Repair ignition system

Yes Next step 5

Check the spark plug of each cylinder to observe whether its

model and gap is in compliance with the specification. No Adjust or replace

Yes Wash the related

components 6




Yes Next step

7 Check whether the intake pressure sensor, air throttle position

sensor and its line are normal. No

Repair circuit or replace

sensor

Yes Failure of replacement 8

Dismantle the fuel injector and check whether there is leakage

or blockage in the fuel injector with cleaning analyzer special

for fuel injector. No Next step

Yes Change fuel 9



Yes Next step 10


timing is in line with the specification. No Repair ignition timing

11 Check whether the operation of the exhaust pipe is smooth. No Repair or replace exhaust

pipe




1.0 Table of Common Malfunction Codes for UAES Control System of 3-Cylinder Engine


P0030 Open-circuit of upstream oxygen sensor heating control circuit

P0031 Short-circuit of upstream oxygen sensor heating control circuit to ground

P0032 Short-circuit of upstream oxygen sensor heating control circuit to power supply

P0036 Open-circuit of downstream oxygen sensor heating control circuit

P0037 Short-circuit of downstream oxygen sensor heating control circuit to ground

P0038 Short-circuit of downstream oxygen sensor heating control circuit to power supply

P0053 Inappropriate heating internal resistance of upstream oxygen sensor

P0054 Inappropriate heating internal resistance of downstream oxygen sensor

P0105 No signal variation of air intake pressure sensor (Frozen)

P0106 Inappropriate air intake pressure sensor

P0107 Short-circuit of air intake pressure sensor to ground

P0108 Short-circuit of air intake pressure sensor to power supply

P0112 Low signal voltage of air intake pressure sensor

P0113 High signal voltage of air intake pressure sensor

P0117 Low voltage of engine coolant temperature sensor circuit

P0118 High voltage of engine coolant temperature sensor circuit

P0122 Out-of-lower-limit of throttle position sensor circuit voltage

P0123 Out-of-upper-limit of throttle position sensor circuit voltage

P0130 Inappropriate upstream oxygen sensor signal

P0131 Low upstream oxygen sensor signal circuit voltage

P0132 High upstream oxygen sensor signal circuit voltage


P0134 Malfunction of upstream oxygen sensor circuit signal

P0136 Inappropriate downstream oxygen sensor signal

P0137 Low downstream oxygen sensor signal circuit voltage

P0138 High downstream oxygen sensor signal circuit voltage

P0140 Malfunction of downstream oxygen sensor circuit signal

P0170 Inappropriate closed-loop control self-learning of off-line testing air-fuel ratio

P0171 Thin closed-loop control self-learning of off-line testing air-fuel ratio

P0172 Thick closed-loop control self-learning of off-line testing air-fuel ratio











P0300 Detection of misfire in various cylinders




P0321 No detection of missing tooth BM signal after certain angle rotation of crankshaft

P0322 No pulse signal of speed sensor (open-circuit or short-circuit)

P0327 Low voltage of knock sensor signal circuit

P0328 High voltage of knock sensor signal circuit

P0340 Inappropriate installation location of phase sensor

P0341 Poor contact of phase sensor

P0342 Short-circuit of phase sensor to ground

P0343 Short-circuit of phase sensor to power supply

P0420 Aged oxygen storage capacity of three-way catalytic converter (out-of-limit of emission)

P0444 Open-circuit of carbon canister control valve control circuit

P0458 Low voltage of carbon canister control valve control circuit

P0459 High voltage of carbon canister control valve control circuit

P0480 Open-circuit of cooling fan relay control circuit (low speed)

P0481 Open-circuit of cooling fan relay control circuit (high speed)

P0501 Inappropriate vehicle speed sensor signal

P0506 Lower idling control speed against target speed

P0507 Higher idling control speed against target speed

P0508 Short-circuit of stepping motor drive pin to ground

P0509 Short-circuit of stepping motor drive pin to power supply

P0511 Open-circuit of stepping motor drive pins

P0560 Inappropriate system battery voltage signal

P0562 Low system battery voltage

P0563 High system battery voltage

P0602 Programming error of electronic control unit

P0627 Open-circuit of fuel pump relay control circuit

P0628 Short-circuit of fuel pump relay control circuit to ground

P0629 Short-circuit of fuel pump relay control circuit to power supply

P0645 Open-circuit of A/C compressor relay control circuit

P0646 Short-circuit of A/C compressor relay control circuit to ground

P0647 Short-circuit of A/C compressor relay control circuit to power supply

P0650 Malfunction of malfunction indicator lamp circuit

P0691 Short-circuit of cooling fan relay control circuit to ground (low speed)

P0692 Short-circuit of cooling fan relay control circuit to power supply (low speed)

P0693 Short-circuit of cooling fan relay control circuit to ground (high speed)

P0694 Short-circuit of cooling fan relay control circuit to power supply (high speed)

P1651 Malfunction of SVS lamp drive circuit

P2177 Out-of-upper-limit of air-fuel ratio closed-loop control self-learning (Medium load zone)


P2178 Out-of-lower-limit of air-fuel ratio closed-loop control self-learning (Medium load zone)





Documents

Manual de Servicio Jac j2