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KNOWYOURSTUFF:gWHAT'S THAT SMELL?

Remember that new-car smell? Actually, new cars haven't had that smellsince manufacturers took the solvents out of the glues in the interior in

an attempt to savea lot of UAW members' livers. Oh well. But there are

plenty ofother smells emanating from your car. Some ofthem are perfectlynormal, even if they're annoying. Other odors are definitely evidence of

Something Wrong. You-or your mechanic-can tell a lot about the sourceofan odor by simply walking around the car. Some odors are only apparentwhen the car is running, others when it's hot, others when it's sitting.

SMELLS LIKE: MAPLE SYRUPWhen: After the engine has warmed or possibly even after it's shut offfor a few minutes.

The Culprit: Coolant containing sweet-smelling (but toxic) ethylene glycolis leaking from somewhere. It could be coming from a radiator or heaterhose or a failed intake manifold gasket or cylinder head. It might be comingfrom a leaky radiator cap or the radiator itself, especially i f you smell it

outside the car. A strong odor inside the passenger compartment

probably means a bad heater core.

SMELLS LIKE: GYM SOCKSWhen: Youturn on the heater/air conditioner fan and you get a whiffof that high school gym locker.

The Culprit: It's good, old-fashioned mildew growing in the moisturecondensing inside your A/C evaporator. And no, drizzling Listerine down

the vents won't fix it, in spite ofwhat your brother-in-law read on theInternet. Cheap solution: Turn off the A/C a mile from home and run

the fan on high to dry the system out.

SMELLS LIKE: HELLWhen: All the time, especially after the vehicle has been sitting after

a long drive.

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Th ulprit:Yes,it really is brimstone, or, as it is usually called today, sulfur.

1 1 li'. 1 11 n gear lube is leaking from the manual transmission, transfer

'1'1\, r Irf rential housing. Sulfur compounds in this oil serve as extreme-

lit I ','" 1/' lu ricants for the gears and can get pretty funky after a few years in',", vie(', I ok for sulfury-smelling dribbles of viscous, oily stuff under the car.IJ ill( ,I(Jilt l Iy,leaks here typically mean a trip to the shop.

n, ulprlt:This is raw gasoline. On older cars-pre-1980 or so-somewlr I. 1 1 t ,'is normal a hot shutoff from fuel after boil inthe carburetor1 1 , 1 ,1 1 I wi. Modern cars have an evaporative-emissions system that's

1 1 1 1 1 1 1 ( ' , lh nour managing editor's deadline schedule, so any fuel smell1.1 ' ,in m thing is wrong. There may be a leak from a fuel-injection

1 1 1 1 1 ' I. ru I-tank vent hose.

I L LIKE: ROTTEN EGGSWh n: /\ny time your engine is running.

fh ulprlt: Hydrogen sulfide inthe exhaust, which is produced by trace

dlllllll1ll r ulfur in gasoline. It's supposed to be converted to sulfur dioxide

I t IVI III t l lytic converter. This may be indicative ofa fuel-injection problem,It 111 r ,lIi I ured by a sharp mechanic. But often it means afailed catalytic

I II I lV I" t r, rh bad news: a new cat is expensive.The good news is it's

1 1 1 1 1 \ Illlly v red under warranty. Check with your dealer.

LIKE: BURNT PAPERII speeds, particularly when you're working your way through

'II ulprlt:TI clutch facing is burning off as the clutch slips.The odor

, II 1 l1 1 l11, nt of smoldering newsprint-like trying to burn the Sunday

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II(cont.)KNOWYOURSTUFF:WHAT'S THAT SMELL?

newspaper all at once inthe fireplace, especially if it's been used to wrap

sardines. The friction material is actually a paper composition, which

explains the papery part of the smell. Either replace the clutch, or learnto stop riding the clutch pedal.

SMELLS LIKE: HOT OILWhen: Your engine is hot.

The Culprit: Oil is leaking onto the hot exhaust manifold. This is an acrid,

burning smell. It's earthier and more nose wrinkling than the odor of

cooking oil used for french fries. Ifit's from a leaky crankshaft seal that's

spraying oil all over, some of it will find the red-hot manifold-but most

will be on the pavement. A leaky valve cover won't necessarily leave a drip

on the floor ifall the oil drizzles onto the exhaust, vaporizing immediately.

Look for smoke and try to stem the leak.

SMELLS LIKE: BURNT CARPETWhen: After you've been using the brakes a lot, or hard, or both.

The Culprit: The brake pads are overheated. This is perfectly normal

after riding the brakes coming down a long mountain pass-but you

should learn to downshift, you flatlander. Ifyou smell this under normal

driving conditions, you've got a dragging brake caused by a seized-up

brake caliper piston. Or maybe youjust left the hand brake on. Checkthe temperature of the brakes by hand-the hot one is probably

the smelliest.

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IIKNOWYOURSTUFF:WHAT'S THAT SOUND?

A moving car is a complex symphony ofsound, most of it reassuring-tires

humming, engine rumbling, tailpipes roaring. But every now and then adissonant note creeps into the mix-and the alert driver's ears prick up:

Did you hear that? Here's a guide that identifies those oddball sounds and

helps you sort out which conditions you can let slide and which ones meanrepairs-and how fast you need to make them.

THUMPTHUMP

THUMPTHUMP

THUMPTHUMP

Where: From one or more tires.When: At low speeds, especially inthe morning; speeds up with car.

What: Flat-spotted tire. As the tire rotates, the flat spot thumps on theground. Nylon-cord tires will flat-spot overnight and make this sound untilthey warm up. It's usually worse in colder weather. Youcan permanently

flat-spot the tires by locking up the wheels, grinding massive amounts ofrubber off the tread inone spot.Urgency: Nada.

Fix: Replace your nylon tires with steel-belted tires. Ifyou've ground down ~your tires like a pencil eraser, you can either live with the vibration until wear P .!reduces the flat-spotting or buy new tires.

FFFFffff ttttFFFF ffff ttttFFFFffff tttt

Where: Under the hood.

When: Most noticeable at idle.

What: An exhaust manifold gasket hasfailed, venting hot exhaust gasesto the air.Urgency: It's not getting better on its own. The blowtorch of corrosivegases will eventually damage the manifold. Oh, by the way: carbon

monoxide from the leak may make you drowsy or dead.Fix: Replace the exhaust manifold gasket before the leak eats a hole

in the manifold.

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~I'r wondering why your Check Engine light is on and why

I orly, this is probably why.Lor replace the line.

Wh r: 11I r Lh center of the car or truck, near the middle.Will II: \,ItI,1111off at traffic lights. Most often heard on pickups with.1 1 1 1 , IIlItlll . II ,ll1slTlissions,not manuals.

Wlllll: 11111\'l1lln that allow the driveshaft to change length where itI I1III1I(hI III Lail haft are binding as you slow down and then releasing

will IIVrlllt1, Iloff.

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II(CONT.) KNOW YOUR STUFF:WHAT'S THAT SOUND?

Urgency: Annoying, but theyall dothat-or at least some of themdo it some ofthe time.

Fix: Packing the spline area with special grease helps for a month or so.Or just sell the car or truck.

ThunkThunkThunkWhere: One or both front corners ofthe vehicle.When: Going around slow, sharp corners under light throttle.

What: A CVjoint that allows your front wheels to turn and still be poweredis loose.The boot has failed and let out all the CVjoint's grease, or maybeit'sjust time for it to wear out.

Urgency: Don't leave town. Don't usealot of throttle around sharp turns.Your car will stop suddenly when thejoint completely fails.Fix: Replace the entire off ending half-axle.

CLUNKWhere: Front end.

When: Initially, when parking; eventually, over small bumps.

What: The balljoint that connects the suspension arm to the uprighthas lost its lubrication and the metal-to-metal contact is wearing it out.Urg enc y: Makean appointment. Avoid bumpy roads, curbs, and potholes.Fix : Replace the balljoint.

GrumbleGrumble

Where: Front of the car.

When: At idle. (Check for weeping coolant at the bottom of the waterpump, too.)

What: Water pump bearings.Urgency: When the bearings fail completely, the fan will pull forward and slicea nice big smile-shaped chunk out of the radiator, making it leak profusely.

Fix: You need a new pump.

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' f {YYIIOOOOOWWwwrrrrrrr

WIl r : Under the hood.

Wh n: Wh never you rotate the steering wheel all the way to the left

(II IIIJ I1\ t ring stop and hold it there.Wh,.t: Iii pr ssure relief valve inside the pump is dumping excess power

'01llllllnq Ilydr ulic fluid back into the reservoir. It's supposed to do that,1111111(I !Il maybe a little more quietly.

Ur 1 1 y: No big deal.

t x: It" n rm I.Actually, you should check the level of power steeringIII!I( 1111\11 pump. Don't hold the wheel hard on the stop like that; it annoysIlntlll',lrliln and is tough on the belt.