d6cc - Fuel System

8/13/2019 d6cc - Fuel System

1/45

Fuel SystemGeneral

Specifications ................................................... FL - 2

Special Tools ..................................................... FL - 3

Description ........................................................FL - 4

External Wiring Diagram Of Unit Injector

(ECU) ................................................................FL -16

Troubleshoot ing ................................................ FL -17

Engine Control System-EletronicEngine Control Unit(ECU)

Replacement ............................................... FL -25

Electronic Unit Injector(EUI)

Components ................................................ FL -26

Inspection ....................................................FL -31

Replacement ............................................... FL -31Priming Pump

Replacement ............................................... FL -34

Overflow Valve

Replacement ............................................... FL -35

Mass Air Flow Sensor(MAFS)

Inspection ....................................................FL -36

Fuel Delivery System-EletronicAccelerator Pedal

Replacement ............................................... FL -39

Fuel Tank

Components ................................................ FL -40

Replacement ............................................... FL -41

DTC TroubleshootingDiagnostic Trouble Codes ................................ FL -42


2/45

General

SPECIFICATIONS

Item Specifications

Fuel pump Type Inner contact gear type

Maximum supply pressure 7kgf.cm

Driving Air compressor shaft driving

Control unit Voltage 24V

Connector 62 pin x 3

Unit injector(Solenoid

valve)

Voltage 90V

Resistance(at 20C) 1.665%(5V), 1.405%(NCV)

Coolant temperature

sensor and Gauge unit

Voltage 5V

Operating range -40C~130C

Connector 3 pin

Intake pressure temp-

erature sensor

Voltage 5V

Operating range Temperature -40C~125C

Pressure (Absolute) 32.5~284 kPa(0.33~2.9kgf.cm)

Connector 4 pin

Crank shaft and Cam-

shaft position sensor

Resistance 860 10%

Operating range 40~3,000 r/min

Connector 2 pin

Air gap 1.0~2.0 mm

Fuel pressure temper-

ature sensor

Voltage 5V

Operating range Temperature -40C~130C

Pressure 0~1000 kPa(0~10kgf.cm)

Connector 4 pin


3/45

SERVICE STANDARDS

Item Standard value

Electric injector Opening pressure Min. 260 bar

Injection pressure Max. 2,000 bar

Idle rotation speed(RPM) 500 20 rpm

Overflow valve opening pressure 4.0 bar or higher

Cam shaft position sensor air gap 1.0~2.0 mm

Crank shaft position sensor air gap 1.0~2.0 mm

Fuel pump discharge amount 500rpm 4 bar(1/min or more)

1900rpm 7 bar(7/min or more)

TIGHTENING TORQUE

Item Tightening torque

N.m kgf.m lb-ft

Overflow valve 33~ 39 3.4~ 4.0 24.7 ~ 29.1

Pipe quick connector 27.4~ 29.4 2.8 ~ 3 20.2 ~ 21.6

Eye bolt(Overflow valve side) 29.4~ 34.3 3 ~ 3.5 21.6 ~ 25.2

Fuel filter mounting bolt 34.3~ 44.1 3.5~ 4.5 25.2 ~ 32.4

LH-Cover mounting bolt(ECU side) 4.9~ 7.8 0.5~ 0.8 3.6 ~ 5.8

ECU wiring cover mounting bolt 7.8~ 9.8 0.8 ~ 1 5.8 ~ 7.2

Fuel return hose mounting bolt(M6) 6.9 ~ 10.8 0.7~ 1.1 5 ~ 7.9

Fuel return hose mounting bolt(M10) 14.7~ 19.6 1.5 ~ 2 10.8 ~ 14.4

ECU mounting bracket attaching bolt 34~ 54 3.5~ 4.5 25.5 ~ 40.0

ECU mounting flange bolt 19~ 27 2 ~ 2.5 13.8 ~ 20.4

Intake pressure temperature sensor 5~ 6 0.5~ 0.6 3.6 ~ 4.4

Camshaft position sensor 8 ~ 10 0.8~ 1.0 5.8 ~ 7.3

Crankshaft position sensor 8 ~ 10 0.8~ 1.0 5.8 ~ 7.3

Fuel pump mounting bolt 10~ 12 1.0~ 1.2 5.8 ~ 8.7

SPECIAL SERVICE TOOL

Tool Shape Use

Rocker arm shaft setting

09245-84100

SDHEM7022D

Installation and removal of rocker arm

shaft


4/45


5/45

EUI (Electronic Unit Injector)

Unit Injector

The unit injector consists of pumping element(A),

controlling component(B), and nozzle(C) as shown in the

illustration. The pumping element(A) generates the fuelpressure as the force from the cam drives the plunger by

way of the rocker arm. The controlling component(B)

controls the operation of the spill valve and needle

control valve by driving the solenoid according to the

commands from ECU. The nozzle element(C) finally

injects fuel into the cylinder by the fuel pressure

delivered.

SGZFL9003L

Operating Theory of Unit Injector

1. Fuel intake

The fuel circuit is open when the spill valve is opened

and fuel comes into pump chamber as the return

spring lifts up the plunger.At this time, the needle of nozzle is closed by the

spring.

SGZFL9004L

2. Fuel discharge

When the rocker arm begins to press plunger, fuel

begins to be compressed in pump chamber.

However, the sudden pressure rise does not occur as

the spill valve is opened. That is, fuel flows throughthe spill valve.

3. Fuel compression start

The fuel in the pump chamber is compressed when

the spill valve(SV) is closed by the signal of ECU.

The fuel pressure starts to rise according to plunger

down.

4. Fuel injection start

When the fuel pressure in the pump chamber

reaches at appropriate level, the needle control valve

is activated by the signal of ECU. At this time, the

fuel injection starts to inject according as the nozzleis opened by the pressure difference between before

and after needle when the pressure of rear of needle

is released.

5. Fuel injection end

The pressure between before and after needle is

equal when the operation of needle control valve is

deactivated by the signal of ECU. And the fuel

injection is terminated as the nozzle is closed by the

spring.


6/45

CONTROL UNIT AND SENSOR

SGZFL9027L

1. MAF sensor

2. Coolant temperature sensor

3. Intake temperature pressure sensor

4. ECU

5. Fuel temperature/ pressure sensor

6. Fuel filter

7. Priming pump

8. Crank position sensor

9. Cam position sensor

10. Injector wiring connector

1. Control unit(ECU)

Control unit(ECU) controls unit injector to inject a fuel

into the cylinder.

Mounted to the cylinder block, it receives information

from accelerator pedal and several sensors and setsthe fuel injection time and amount into cylinder.

The control unit calculates the injection fuel amount

and time when spill valve of injector is closed.

The fuel injection amount into combustion chamber is

adjusted or limited by the following conditions.

- Fuel amount needed (Fuel injection amount is set

by the driver's operation)

- Fuel injection limit (Fuel injection amount is set by

engine condition)


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2. Engine control

1) Control of fuel injection amount

The fuel injection amount is calculated and set by

the engine load, speed and fuel injection amount

is compensated in through the input of varioussensors about the engine condition.

SGZFL9005L

2) Limit of fuel amount

Control unit limits fuel amount requested by the

driver for safety and engine protection under the

following conditions if necessary.

- In case of excessive smoke

- When engine overheats

- In case of excessively high speed

- When fuel requested exceeds the maximum

injection quantity

- When engine speed is excessively high

- When engine speed limit is needed in cold

state

- When EGR is defective

3) Limit of maximum engine speed

When coolant temperature is lower than set value

or vehicle speed sensor is zero, maximum speed

of engine is limited to protect engine from high

temperature and mechanical damage.


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4) Control of fuel injection timing

Fuel injection time is set depending on engine

speed and requested fuel amount and is

compensated based on the engine state from

sensors.

SGZFL9006L


9/45

5) Cold starting control

Engine control unit minimizes white smoke

generating at cold start by injecting optimum fuel

amount into engine at cold start and increases

engine temperature to normal running

temperature in a short time.

And it controls heater to heat up air flowing into

engine, which is divided into preheating before

starting and post-heating after starting.

1. Air heating control

a. Intake air heating at cold start

- Reducing the smokes due to incomplete

combustion

- Early warming of engine

- Startability improvement

ECBFL5008A

6) Control of idle speed

1. Idle adjustment: Keep the specified rpm

regardless of load.

2. Adjustment of unstable idling: Adjust idle

speed to the programmed value in ECU when

idling is unstable

- Increase or decrease rotations to the

preset ranges specified by driver

- Store the idle value before adjustment.

SGZFL9007L


10/45

3. Idle adjustment

- Idle adjustment at cold: Increase idle

speed after cold starting to expedite the

warming up.

- Increase idle to prevent batterydischarging when the air conditioner is on.

- Increase idle to quicken the charging rate

if battery voltage is low.

4. Idle adjustment at cold start

7) Manual adjustment of idle

Idle adjustment can be manually using

self-diagnostic switch mounted to driver seat.

For the manual adjustment of the idle, following

conditions should be met.

a. Vehicle should be stopped securely.

b. There should be no acceleration pedal signal.

c. Foot brake should be applied securely.

d. It should be at idle state and PTOshould not

be in running state

ECBFL5011A

Driver can set desirable idle speed as mentioned

above. (500 to 800 rpm)

8) Output limit by the fuel pressure

Function: When fuel pressure drops lower than

the value set during regular engine operation, it

reduces the fuel amount requested to protect the

engine and gives driver a warning signal at the

same time.

3. Vehicle control function

1) Cruise vehicle speed control

1. Function: Drives the vehicle within the

specified speed.

2. Operating conditiona. Operation of cruise control switch

b. Brake and clutch pedal are not pressed.

c. Safety switch is turned off.

d. Brake is in normal condition.

e. When vehicle speed is 40 km/h or higher.

3. Releasing condition

a. Releasing of cruise control switch

b. Brake and clutch pedal are pressed

c. If the vehicle speed is lower than the

minimum speed by cruise control function,

cruise is released automatically if one of

the above conditions is met.

d. Transmission retarder is operated

The cruise control will be released if one

of above conditions is met.

4. If the vehicle speed exceeds the specification,

exhaust brake and engine brake operate in

sequence. In addition, fuel amount is limited

by the smallest value among maximumengine

speed, torque performance and smokerestriction.

2) Limit of maximum vehicle speed

1. Function: Limit maximum vehicle speed by

restriction of fuel supply

2. Control method

a. Operated by set program in sequence.

b. If the fuel is not applied and the vehicle

speed is higher than specified one on the

downhill, the exhaust brake and the jake

brake work successively. This condition

prevents the vehicle speed from

increasing excessively.


11/45

3) Door safety switch

1. Function: While the safety switch installed on

the bus door is operating, ECU keeps the

engine idle by ignoring the accelerator pedal

signal to prevent the risk of vehicle moving.

2. Circuit operation diagram

ECBFL5012A

4) FAIL SAFE function

1. Pedal sensor

a. Condition: Error occurrence at

acceleration pedal sensor and idle rotation

switch

b. Limit of pedal function

2. Fuel temperature sensor : Use setup value

3. Intake temperature sensor: Use setup value

4. Fuel pressure sensor: Use setup value

5. Outdoor temperature sensor: Use setup value

6. Intake pressure sensor: Use setup value

7. Atmosphere pressure sensor: Use setup value

8. Vehicle speed sensor

a. Fail judgment conditions

- When fuel amount is more than the setup

value

- When engine rotations are higher than the

setup value

- When coolant temperature is higher than

the setup value

- When PTO is not operating

- When vehicle speed is zero

- When clutch is not operating

9. Use crank sensor at breakdown of cam

sensor and signal value of cam sensor at

breakdown of crank sensor

10. Engine coolant temperature sensor : Use

setup value

5) PTO

1. Function: Keeps engine rotation speed regular

regardless of load to operate the auxiliaryunit.

2. Operating condition

a. When cruise / PTO operating switch is ON

b. When the vehicle speed is lower than

selective setup value (10km/h in general

and engine running state)

c. When PTO is adjustable from the driver

seat or outside of the vehicle


12/45

3. Operation: When setup time (approximately 1

sec.) has passed, PTO governor controls

rotation speed of engine into initial engine

rotations of PTO. At this time, PTO indication

lamp turns on to inform driver.

4. Release: When cruise / PTO operating switch

is OFF, ECU slows down the engine rotations

to be at idle speed.

5. When PTO is adjustable from the driver's seat

or outside of the vehicle

6. PTO engine rotations increase when

acceleration pedal is applied and return to

standard PTO rotations when it is released.

7. PTO engine rotations decrease to the initial

PTO speed in operating one or both of clutch

and brake at the same time and return tostandard PTO rotations when it is released.

6) Cruise Control / PTO Enable Switch

Set Cruise Control or PTO operation of special

vehicle to ON/OFF.

7) Cruise Control / PTO / Idle Control Switch

Used as control switch at operation of Cruise

Control or PTO of special vehicle, idle control

switch at idle and error code checkup switch at

engine halt.

8) Exhaust brake and jake brake solenoid valve

Control unit controls solenoid valve based on the

switch operation of driver or engine state to

operate exhaust brake or jake brake.

9) Power mode switch

The driver can select fuel economy mode and

power mode by operating the switch.

The economy mode is to optimize fuel ratio but

the power mode is to maximize output under

engine operation condition.


Engine coolant temperature sensor is a resistancetype, mounted to thermostat housing.

ECU judges damage state of engine on the basis of

output voltage of this sensor and controls fuel amount

properly based on the engine coolant temperature.

5. Intake pressure temperature sensor

Intake pressure temperature sensor measures

pressure and temperature of air supplied for engine

and sends voltage signal to ECU, mounted to intake

manifold.

ECU adjusts the injection timing and fuel amount

according to the air pressure and temperature

informed by the sensor.

6. Crankshaft position sensor

Crankshaft position sensor generates pulse signal by

projection of the fly-wheel when fly-wheel rotates and

sends it to ECU, mounted to the left side of fly-wheel

housing.

ECU calculates the location and speed of engine,

using generated pulse signal and controls fuel

injection time and amount on the basis of them.7. Camshaft position sensor

Camshaft position sensor generates pulse signal

from sensor wheel installed at the end of camshaft

and sends it to ECU, mounted to the left side of

timing gear cover of cam shaft.

A pulse signal is generated each cylinder and

becomes standard of TDC by cylinder. Another pulse

signal is generated to have cylinder No.1 recognized

at the location of cylinder No.1.

ECU recognizes cylinder No. and TDC then,

determines injection order and time.

8. Fuel pressure/ temperature sensor

Measure the fuel temperature and the pressure.

Output is corrected according to the change of fuel

temperature as the fuel varies depending on

temperature.

9. Mass air flow sensor(MAF sensor)

The intake air voluem sensor is used to control the

EGR after measuring the intake air volume and

temperature coming from the engine

10.Fan clutch controlECU measures engine coolant temperature and

controls fan clutch electrically to maintain coolant

temperature constant. Electronic fan clutch control

helps improve fuel consumption ratio by minimizing

the operation of cooling fan and reducing power loss.

- Two steps control type: This is the type to control

cooling fan one step or two steps according to

coolant temperature.

- The electronic fan clutch helps to improve fuel

ratio by reducing power loss due to fan operation.


13/45

ARRANGEMENT OF CRANK SENSOR WHEEL AND CAM SENSOR WHEEL IN TDC

ECBFL5013A

- Crank sensor wheel is used to recognize the enginespeed and status of engine cylinder and cam sensor

wheel is used to recognize position of cylinder No.1

together with crank signal.

- Crank sensor wheel teeth are composed at intervals

of 6 and 2 teeth are missed at interval of

120Camshaft is composed of 60as a standard.

- Camshaft has total 7 teeth and a tooth is added at

No.1 to recognize standard of cylinder No.1.

- Cylinder No.1 of camshaft is located after 15 from

the added tooth and TDC of cylinder No.1 is located

after 34.5from tooth No.1.


14/45

CONTROL RELAY

When the start switch is ON, battery voltage flows from

starting switch to control unit. At this time, power

transistor is switched on to control relay coil.

Then, control relay switch is ON and main power issupplied from battery to control unit through control relay

switch.

ECBFL5014A

PRIMING PUMP

Priming pump is mounted on the fuel filter head and used

to discharge fuel and air in fuel system manually at initial

engine starting or after fuel filter replacement.

Priming pump mounting torque:27~29Nm(2.8~3kgf.m, 20.4~21.8lb-ft)

SGZFL9008L

FUEL FILTER

Fuel filter is spin-on type so that the element

replacement is easy.

It removes impurities in fuel supplied from fuel supply

pump.Joint torque of cartridge :

32~ 34Nm(1.2 ~ 1.6kgf.m, 8.7~11.6lb-ft)

SGZFL9009L


15/45

OVERFLOW VALVE

Overflow valve is mounted on the cylinder head fuel

injection port.

It controls fuel pressure in fuel gallery.

Opening pressure of overflow valve:3.0bar and more

Joint torque of overflow valve:

402 Nm(40.2 kgf.m, 28.91.5 lb-ft)

SGZFL9010L


16/45

EXTERNAL WIRING DIAGRAM OF UNIT INJECTOR (ECU)

SGZFL9011L


17/45

Troubleshooting

SELF-DIAGNOSIS

The ECM monitors the input/output signals (some signals

at all times and the others under specified conditions).

When the ECM detects an irregularity, it records thediagnostic trouble code, and outputs the signal to the

Data Link connector. The diagnosis results can be read

with the scan tool or Flash code. Diagnostic Trouble

Codes(DTC) will remain in the ECM as long as battery

power is maintained.

NOTICE

The scan tool can erase the diagnostic trouble codesin

the memory only.

INSPECTION PROCEDURE(SELF-DIAGNOSIS)

NOTICE

1. When battery voltage is low, diagnostic trouble

codes can not be read. Be sure to check the battery

for voltage and other conditions before starting the

test.

2. Diagnosis memory is erased if the battery or the

ECM connector is disconnected. Do not disconnect

the battery before the diagnostic trouble codes are

completely read.

You can erase the DTC codes by using Hi-SCAN

after completing inspection or repair.

USING HI-SCAN TOOL

1. Turn OFF the ignition switch.

2. Connect the Scan Tool to the data link connector.

3. Turn ON the ignition switch.

4. Use the scan tool to check the diagnostic troublecodes.

5. Repair the fail parts from the diagnosis chart.

6. Erase the diagnostic trouble code.

7. Disconnect the scan tool.

NOTICE

The scan tool can erase the diagnostic trouble

codes in memory only.

It is possible to erase the DTC codes only with

key ON without starting the engine.


18/45

USING FLASH CODE

Check by "Check ENG" lamp on the instrument panel

Engine system provides error code inform engine failure

directly without scan tool.

Check the trouble of the error code as follows.

1. Stop the engine

2. Turn the starter to ON position

3. Check that the "CHECK ENGINE" lamp in the cluster

is turned on after pressing SET/INC or REC/DEC

switch approx. 3 sec. or more.

4. Error code is displayed in turn as follows whenever

DEC switch is ON.

5. Previous error code is displayed when INC switch is

ON.6. Refer to error code table and check the trouble and

cause of failure for troubleshooting.

ECBFL5019A


19/45

TROUBLESHOOTING

Symptom Probable cause Remedy

Engine

does not

start

Control sys-

tem

ECU main relay does not operate Check the ECU relay and the power circuit

Poor contact of the ECU or the engine Check the circuit

Disconnection of the ECU or the injector conn-

ector Check the connector connection

ECU malfunction

Check the ECU using the Hi-Scan/

Injector compulsory test/

If necessary, replace the ECU

Starter operation malfunction Starter switch, neutral switch, service switc-

h circuit and operation check

Immobilizer system check

Fuel systemMalfunction of over flow valve

Check the opening pressure of the over flow/

If necessary, replace the over flow valve

Lack of fuel Check the amount of fuel in the fuel tank

Fail of the fuel supply pump

Check the fuel supply pump check valve and t-

he shaft for damage/

If necessary, replace them

Poor supply due to the fuel supply hose kink Check the fuel intake system

Others Malfunction of the air heater Check the air heater relay and the ECU

Air in fuel system Bleed the fuel system

Poor idle

Malfunction of injector

Check the injector variation by acceleration te-

st/If necessary, replace the injector

Air in fuel system Check the fuel line

Fail of the accelerator input signal Check and replace the pedal sensor

White smokeFuel leak to the combustion chamber

Check the injector tube and leak

If necessary, replace the injector.

Air heater malfunction Check the heater relay and ECU

Incorrect injection timing due to ECU damage Check the ECU


Black smoke Malfunction of injector Check the injector by acceleration test

Fail of intake pressure sensor Check the sensor using a Hi-Scan/

Check the sensor output data

Incorrect injection timing due to ECU damage Check the ECU



20/45

Symptom Probable cause Remedy

Low engine power out-

put

(Poor acceleration)

Malfunction of accel pedal Check the accel pedal output data if necessary

, replace the accel pedal

Malfunction of water temperature sensor or en-

gine overheated

Check the water temperature sensor using a Hi

-Scan/

Check the engine cooling system, fan and ther-

mostat

Low fuel pressure

Check the fuel pressure sensor using a Hi-Sc-

an/

Check the fuel system(fuel pump, filter, over fl-

ow valve etc.)

Fail intake pressure sensor or abnormal intake

pressure

Check the intake pressure sensor using a Hi-

Scan/

Check the intake system(Intercooler, intake ho-

se etc.)Freezing fuel in winter time Check the fuel for wax and fuel condition

Electronic fan clutch inoperative Check the fan clutch circuit

Check the engine overheat using a Hi-scan

Malfunction of EGR system Check the EGR system using a Hi-scan

Malfunction of the intake mass air flow sensor

Check the intake mass air flow sensor using a

Hi-scan

Check the air filter


21/45

ACCELERATION TEST

With the engine installed to the vehicle, the injector

and the combustion performance can be inspected

using a Scan tool and the ECU.

Description for Acceleration Test Mode- Comparison of the engine power variation for

each cylinder

- Measurement of the acceleration time by

accelerating the engine with the injectors stopped

one by one.

(Check if any cylinder affects the engine

acceleration.)

- At the engine idle, with one cylinder stopped the

EUI injection, accelerate the engine with five

cylinders. Then measure the acceleration time

until the 60th times of fuel injection.

- For each cylinder, repeat the above procedure

and measure the each acceleration time.

- Compare the measured value relatively and print

the data.

Then evaluate the engine power effect for each

cylinder by the compared result.

- All the above procedures are performed in the

acceleration test mode automatically and the

result is displayed on the Hi-Scan with the figure

and the graph.

Condition of the Acceleration Test

- When engine is idling(500 rpm)

- Engine warm-up(Coolant temperature 60C over)

- No engine load(Air-conditioning, Electrical

mechanism etc.)

How to use the Scan tool

1. When the engine is idling(500 rpm), release the

engine load such as air-conditioning.

2. Connect the Scan tool and check the control unit.

Then select the acceleration test mode.3. Check the message on the screen and if it is

correct, press the enter key.

4. As indicated on the screen, press the accel pedal

fully and press the enter key.

5. Engine will perform the acceleration test

automatically 6 times. During the test, keep the

accel pedal pressed fully.

6. After completing the test, the result will be

displayed on the screen automatically.

- After checking the result, turn off the engine.

ANAL YSIS OF THE TEST RESULT

- If the figure or the graph displayed on the screen of

the Hi-Scan is low relatively, a performance

deterioration of injector and a poor combustion are

suspected.

- If the result value is much low than them of the other

cylinders, inspect the EUI of each cylinder or replace

the cylinder with a new one.

- If necessary, collect information of the overhaul

history and a compressive force test and then

analysis and judge the test result.

NOTICE

Be sure to check the coolant temperature is 60 C

over because engine warm-up can affect the

result of test.

After performing the test, the pedal is notoperated properly, however, this is normal

condition.If the engine is turned off and on

repeatedly, the pedal operates properly.

Judge the test result by the relative comparison

and the total average for each cylinder.

The average of the absolute value is affected by

the engine condition(Load, coolant temperature

etc.).

Therefore, judge the test result by the relative

comparison in priority.

Use this as reference material to inspect the

injector and the combustion performance of the

related cylinder.

After overhauling the engine, be sure to perform

this test to inspect cylinders operate properly.

COMPRESSION TEST

Inspection for the state of compressive force of the

engine each cylinder using a Hi-scan and ECU on the

vehicle.

EXPLANATION FOR COMPRESSION TEST

MODE- Characteristic comparison of compressive force for

each cylinder

- During engine cranking, measure the engine speed

rate by the compressive resistance from the cylinder.

(With the compressive force test mode, no fuel

injection)


22/45

HOW TO USE HI-SCAN

1. With the engine key turned on, connect the Hi-Scan

and check the control unit.

Then select the compression test mode.

2. Check the message displayed on the screen, if it iscorrect press the enter key.

ECBFL5025A

3. As indicated on the screen, press the key and crank

the engine.

ECBFL5026A

4. After completing the test, compare the engine speed

rate for each cylinder by pressing the keys(F1, F2,

F3..) in sequence.

ECBFL5027A

ANAL YSIS OF TEST RESULT

- After completing the test, the graph of the engine

speed rate for each cylinder will be displayed on the

screen of the Hi-Scan.

- When the engine is in the normal condition, the graph

tendency is almost identical.

However, when a certain cylinder exhibits abnormal

compressive force characteristic, the graph tendency

is quite different from normal compressive force

characteristic.

- If the graph tendency is abnormal, inspect the

compressive system including the piston ring and the

valve to prevent a malfunction of the compressive

system.


23/45

FUEL SYSTEM DRAINING

1. Clean around air vent of cylinder head side and fuel

filter side.

ECBFL5028A

FUEL CHARGE AND AIR BLEEDING

1. After engine assembly/disassembly or fuel bleeding

(If fuel is eliminated completely in fuel line)

1) Clean around the air vent of fuel filter and

cylinder head.

2) Unscrew air vent bolt on fuel filter head a little.

SGZFL9012L

3) Perform pumping works, using priming pump on

fuel filter until fuel begins to drain from air vent

cock.

4) Close bolt when air has been eliminated

completely in fuel discharged to fuel filter air vent

5) Unscrew air vent bolt at cylinder head front.

ECBFL5028A

6) Close cock after pumping until air is eliminated in

fuel in the same way as described in the Clause

3).

7) Execute the cranking when the above works are

all done.

Crank it for the time for enough (10 to 15 sec.)

and several times until engine starts.(about 3 to 5

times, if fuel has been eliminated fuel line,

especially if fuel in injector is eliminated

thoroughly, sufficient cranking is necessary from

air discharge to start the engine)

Cranking time should not exceed 15 sec. because

cranking for a long time influences badly on

starter motor. Keep the interval of approx. 30 sec.

until the next cranking to prevent starter motor

from overheating.

8) When engine starts, wait until engine becomes

stable, pedaling accelerator (Approx. 1000rpm).


24/45

2. When replacing a fuel filter element (If fuel is filled in

cylinder head)

1) Clean the fuel filter.

2) Unscrew air vent in fuel filter and remove the

pressure from fuel line.3) Replace the filter element.

NOTICE

Check if the gasket is placed on element

when replacing.

Apply oil to gasket and tighten it sufficiently

by hand.

Tightening torque : 4.40.2 kgf.m

SDCFL8032D

4) Perform pumping until fuel drains from air vent,

using priming pump.(In case of filling fuel in new

cartridge before mounting, pumping time can be

reduced.)

5) Close air vent bolt

SGZFL9012L

6) Perform cranking and start the engine

(Air discharge of cylinder head is not necessary

when replacing a filter and engine starts with just

cranking once in general)


25/45

Engine Control System-Electronic

Engine Control Unit(ECU)

REPLACEMENT OF CONTROL ECU1. Remove the control ECU(A).

SGZFL9013L

2. When replacing the unit injector of the control ECU,

be sure to re-input the compensation value using a

scan tool.

CAUTION

B e s ur e t o mat ch t he c om pen sat ion v al ue

indicated on the injector connector and the i nputdat a of t he c ont rol ECU f or t he en gi ne

performance and t he exhaust gas.

SGZFL9014L


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Electronic Unit Injector(EUI)

Components

SGZFL9015L

1. MAF sensor


3. Intake temperature pressure sensor

4. ECU

5. Fuel temperature/ pressure sensor

6. Fuel filter

7. Priming pump

8. Crank position sensor

9. Cam position sensor

10. Injector wiring connector

11. ECU engine side connector(E65-1)

12. ECU engine side connector(E65-2)

13. ECU chassis side connector(C121)

14. EDU

15. EDU connector(E59)


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Connector(E65-1)

SGZFL9023L


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Connector(E65-2)

SGZFL9024L


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Connector(C121)

SGZFL9025L


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EDU co nnecto r(E59)

SGZFL9026L


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Inspection

INSPECTION OF INJECTOR (EUI)COMPONENTS

[Checking condition]

1. Turn off the ignition switch.

2. Apply the parking brake.

3. Separate ECU connector and connect tester to the

cable harness

4. Perform a test using a multi-meter.

Replacement

REPLACEMENT OF UNIT INJECTOR

CAUTION

1. Be sure to replace the injector at the service

center designated by Hmc.

1. Do not operate the injector while running the

engine because the injector generates the

high voltage over than 50 volts. However,

w hen t he i nj ect or s houl d be oper at ed

inevitably, be careful with an electric shock.

2. When removing t he used injector, be sure to

wear the protective gloves.

At th e hi gh temperatu re ov er th an 315C, the

surface of the injector can be carbonized or

sticky, which cause hydrofluoric acid.

When removing the injector from the engine,

be sure to wear protective gloves to protect

the skin.

1. Remove rocker cover

CAUTION

Be careful for unit injector cable harness not to

be d amaged.

SGZFL9017L

2. Remove the injector cable.

SGZFL9016L

3. Remove cam cap bolts.

NOTICE

Separate bolts in turn to prevent rocker arm shaft

from bending.

ECBFL5034A


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4. Remove rocker arm shaft using the special

tool(09245-84100).

ECBFL5035A

5. Drain fuel in cylinder head according to fuel draining

procedure.

CAUTION

Be sure to drain the fuel in the cylinder head

before removing the unit injector to prevent the

fuel in the combustion chamber from i nflowing.

6. Clean around the unit injector to replace.

7. Unscrew the injector clamp bolt, remove clamp and

then remove the injector carefully.

CAUTIONWhen removing the used injector, be sure to

wear protective gloves.

ECBFL5037A

8. Fix protecting sleeve after removing unit injector.

9. Insert sealing clamp into cylinder head fuel gallery.

NOTICE

Check if sealing clamp is inserted properly at its

place.10.Remove the sealing clamp, and then clean unit

injector hole in cylinder head.

11.Replace O-ring with the new one in the unit injector

and apply engine oil.

Check if it is installed properly in between valve

spring and tighten the unit injector mounting bolt to

the specific torque.

CAUTION

When replacing the injector, be sure to replace

the O-ring with a new one.

[Specific torque]

When replacing other than nozzle tube (when replacing

injector only) : 18 N.m(1.8 kgf.m) +60

When replacing nozzle tube:

First : 18 Nm(1.8 kgf.m) + 60 + 60 Loosen completely

in 2 min.

Second : 18 Nm(1.8 kgf.m) +60

12.Apply engine oil to the cam-shaft rob and the valve

bridge and install the rocker arm shaft using the

special tool(09245-84100).

ECBFL5035A


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13.Install the unit injector

CAUTION

When replacing the unit injector with a new one,

be sure to consider the compensation value of

trim setting code indicated on the top surface ofthe injector connector using a scan t ool.

B e s ur e t o mat ch t he c om pen sat ion v al ue

indicated on the injector connector and the i nput

dat a of t he c ont rol ECU f or t he en gi ne

performance and t he exhaust gas.

SGZFL9014L

14.Connect cable to the unit injector.

Injector pre-stroke : 0.750.15 mm

15.Check if rocker arm shaft is properly mounted after

tightening the cam cap bolts.

Adjust the clearance of the valve and the injector

after tightening the cam cap bolt to the specific

torque.

SGZFL9018L

SGZFL9019L

16.Install the rocker cover.

17.Perform fuel bleeding following the procedure.

18.Run the engine for about 10min at idle to bleed the

air in the system.


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Priming Pump

Replacement

REPLACEMENT OF FUEL FILTER

1. Unscrew the air vent bolt to eliminate remainingpressure in fuel filter.

2. Clean the fuel filter around.

SGZFL9020L

3. After disconnecting the fuel line, remove the

mounting bolt and then detach the fuel filter.

4. Perform the fuel charge and air bleeding.

5. Start engine and run the engine at idle for about

10min to bleed air remaining in the system.

REPLACEMENT OF FUEL PUMP

1. Unscrew air vent bolt loosely to eliminate remaining

pressure in fuel pump.

SGZFL9021L

2. Clean the fuel pump around.

3. Disconnect fuel line.

4. Loosen fuel pump bolt and remove fuel pump.

5. Apply oil to O-ring of new fuel pump and install it.

Tightening

torque of fuel pump bolt:

10~12Nm(1.0~1.2kgf.m, 7.3~8.7lb-ft)

6. Install fuel line.

7. Perform fuel charge and air bleeding (up to fuel filter).

8. Start engine and run the engine at idle for about

10min to bleed air remaining in system.


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Overflow Valve

Replacement1. Clean the overflow valve around.

ECBFL5053A

2. Place container under hose of air vent hole at fuel

filter head and loosen air vent bolt.

ECBFL5028A

3. Disconnect fuel line from overflow valve.

4. Remove overflow valve.

ECBFL5053A

5. Clean the contact points of cylinder head and mount

new overflow valve.

Tightening torque of overflow valve :

402 Nm(40.2 kgf.m, 28.91.5 lb-ft)

6. Install fuel line and perform fuel charge and air

bleeding (Refer to method if the fuel is completely

eliminated from fuel line).

7. Start the engine and run the engine at idle about 10

minutes to bleed air remaining in system.


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Mass Air Flow Sensor

Inspection

Description

MAF sensor is built into the vehicle for controlling theEGR system precisely.

The air flow, supplied to an engine, is measured lower

than actual air flow due to contamination of MAF sensor.

Then EGR system can't be controlled precisely.

To prevent it in advance, you have to clean the MAF

sensor periodically.

Clean the MAF sensor every 6 months or 60,000 km

using "Carb and Choke Cleaner".

Visual inspection

SGZFL9028L

CAUTION

1. Don't impact or drop the sensor when replacing

it .

2. Don't use the sharp t ool at removing the sensor,

otherwise t he O-ring may be damaged.


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Procedure and caution when cleaning the sensor

SGZFL9029L


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CAUTION

1. To remove the O-ring of MAF sensor

- Remove the O-ring of MAF sensor to prevent

it from damage by cleaning spray and clean

the sensor element.

SGZFL9030L

2. Procedure of atomizing the spray

- Atomize the spray to the end part of sensor

housing.

- Don't use the nozzle of spray to prevent the

sensor element from damage.

- Ato mize th e spr ay with 2~3 t imes f or 2~3

seconds.

SGZFL9031L

3. To dry the sensor element

- Usin g th e air g un : Belo w 5 b ar , with in 30

seconds.

- After atomizing the spray, dry the sensor like

below picture for 20 minutes.

SGZFL9032L

4. To install the O-ring of MAF sensor

- Install the O-ring after completing to dry the

sensor.

SGZFL9030L


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Fuel Delivery System-Electronic

Accel erator Pedal

Replacement

Ac cel erator pedal(Bus )

1. Turn the ignition key off and disconnect battery

negative(-) cable.

2. Remove the accelerator sensor connector.

3. Remove the accelerator pedal assembly(A) after

removing accelerator pedal mounting bolt.

ECBFL5062A

4. Installation is in the reverse of removal.

Tightening torque: 18.6~27.5 Nm

(1.9~2.8 kgf.m, 13.7~20.3 Ib-ft)


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Fuel Tank

Components

SGZFL9022L

1. Fuel tank

2. Air compressor

3. Fuel pre-filter

4. Fuel pump


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Replacement

Fuel tank

1. Park the vehicle on a flat road surface and stop the

engine. Disconnect battery negative(-) cable.

2. Remove the sender connector on the upper of thefuel tank.

3. Remove return hose and feed hose.

4. Remove the fuel hose connecting to the fuel tank.

5. Support the fuel tank assembly with a jack and

loosen the fuel tank bracket of lower part and the

band mounting nut. And remove the fuel tank.

6. Installation is in the reverse of removal.

NOTICE

When installing fuel cap rotor to fuel cap holder, turn

the ignition key clockwise 15

or so with it pressedafter inserting the ignition key into fuel cap rotor(A).

After installed, repeat to lock and unlock the ignition

key five times so that grease is spread evenly.


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DTC Troubleshooting

Diagnostic Trouble Codes [DTCs]

No DTC Description

1 P0016 Camshaft - Crankshaft position Correlation

2 P0017 Crankshaft - Camshaft Position Correlation

3 P0072 Ambient Air Temperature Sensor Circuit Low

4 P0073 Ambient Air Temperature Sensor Circuit High

5 P0102 Mass or Volume Air Flow Circuit Low Input

6 P0103 Mass or Volume Air Flow Circuit High Input

7 P0107 Manifold Absolute Pressure Circuit Low Input

8 P0108 Manifold Absolute Pressure Circuit High Input

9 P0112 Intake Air Temperature Sensor Circuit Low

10 P0113 Intake Air Temperature Sensor Circuit High

11 P0117 Engine Coolant Temperature Sensor Circuit Low

12 P0118 Engine Coolant Temperature Sensor Circuit High

13 P0182 Fuel Temperature Sensor Circuit Low

14 P0183 Fuel Temperature Sensor Circuit High

15 P0217 Engine Coolant Over Temperature Condition

16 P0335 Crankshaft Position Sensor Circuit

17 P0340 Camshaft Position Sensor Circuit

18 P0401 Exhaust Gas Recirculation Flow Insufficient Detected

19 P0402 Exhaust Gas Recirculation Flow Excessive Detected

20 P0475 Exhaust Brake, Open Circuit

21 P0480 Fan 1 Control Circuit

22 P0481 Fan 2 Control Circuit

23 P0500 Vehicle Speed Sensor

24 P0541 Intake Air Heater Circuit Low

25 P0542 Intake Air Heater Circuit High

26 P0543 Intake Air Heater Circuit Open

27 P0562 System Voltage Low

28 P0563 System Voltage High

29 P0601 Internal Control Module Memory Check Sum Error

30 P0611 Fuel Injector Control Module Performance

31 P0615 Starter Relay Circuit Open

32 P0616 Starter Relay Circuit Low

33 P0617 Starter Relay Circuit High


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No DTC Description

34 P0642 Sensor 5V Reference Under Range

35 P0643 Sensor 5V Reference Over Range

36 P0652 Pedal Sensor Reference Voltage Circuit Low

37 P0653 Pedal Sensor Reference Voltage Circuit High

38 P0668 ECU Internal Temperature Sensor Circuit Low

39 P0669 ECU Internal Temperature Sensor Circuit High

40 P0685 ECU Power Relay Control Circuit /Open

41 P0691 Fan 1 Control Circuit Low

42 P0692 Fan 1 Control Circuit High

43 P0693 Fan 2 Control Circuit Low

44 P0694 Fan 2 Control Circuit High

45 P1087 Fuel Pressure Derate Level 1



48 P1106 Air Plausibility Fault

49 P1201 Injector 1 needle valve open circuit

50 P1202 Injector 1 needle valve short circuit across injector

51 P1203 Injector 1 needle valve low side short circuit to ground

52 P1204 Injector 1 needle valve low side short circuit to battery voltage


















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No DTC Description





73 P1225 Injector 1, 3, or 5 needle valve high side short circuit to ground

74 P1226 Injector 1, 3, or 5 needle valve high side short circuit to battery voltage

75 P1227 Injector 2, 4, or 6 needle valve high side short circuit to ground

76 P1228 Injector 2, 4, or 6 needle valve high side short circuit to battery voltage

77 P1229 Injector 1 spill valve open circuit

78 P1230 Injector 1 spill valve short circuit across injector

79 P1231 Injector 1 spill valve low side short circuit to ground

80 P1232 Injector 1 spill valve low side short circuit to battery voltage





















101 P1253 Injector 1, 3, or 5 spill valve high side short circuit to ground

102 P1254 Injector 1, 3, or 5 spill valve high side short circuit to battery voltage

103 P1255 Injector 2, 4, or 6 spill valve high side short circuit to ground


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No DTC Description

104 P1256 Injector 2, 4, or 6 spill valve high side short circuit to battery voltage

105 P1403 EGR EDU power-up sequence.

106 P1562 The battery voltage is too high

107 P1653 Check Engine/Diagnostics Lamp, open circuit

108 P1654 Check Engine/Diagnostics Lamp, shortcut to ground

109 P1655 Check Engine/Diagnostics Lamp, shortcut to battery

110 P1656 Engine Hot Lamp Output Control Circuit

111 P1657 Engine Hot Lamp, shortcut to battery

112 P1658 Engine Hot Lamp, shortcut to ground

113 P1666 Fault on the hardware watchdog

114 P1680 Memory fault with customer data checksum

115 P1681 Memory fault with calibration data checksum

116 P1700 Engine brake 1, open circuit



119 P2109 Pedal Position Sensor Minimum Stop Performance

120 P2110 Pedal Position Sensor Maximum Stop Performance

121 P2147 Injector boost voltage under range

122 P2148 Injector boost voltage over range

123 P2228 Barometric pressure circuit low

124 P2229 Barometric pressure circuit high

125 P2541 Low Pressure Fuel System Sensor circuit Low

126 P2542 Low Pressure Fuel System Sensor circuit High

127 P2609 Intake Air Heater System Performance

128 U1169 EGR Valve Stick Fault

129 U1170 EGR Actuator Terminal Coil Open Circuit

130 U1171 EGR Actuator Over Current

131 U1180 EGR Actuator Battery Supply Error

132 U1182 EGR Valve Position Error

133 U1183 EGR Message Transmit Fault Error

Documents

d6cc - Fuel System