The more you know about your vehicle, the more likely you can head off repair problems. You can detect many common problems by using your senses: eyeballing the spot where you parked your car, listening for strange noises, sensing a difference in the way it handles, or even noticing unusual odors.
LOOKS like trouble
Small stains or an occasional drop of fluid under your vehicle may not mean much. But wet spots deserve attention; check puddles immediately. Identify fluids by their color and consistency:
* Yellowish-green, pastel blue, or florescent orange indicates an overheated engine or an antifreeze leak caused by a bad hose, water pump, or leaking radiator.
* A dark brown or black oily fluid means the engine is leaking oil. A bad seal or gasket could cause the leak.
* A red oily spot indicates a transmission or power steering fluid leak.
* A puddle of clear water usually isn't a problem. It may be normal condensation from your vehicle's air conditioner.
SMELLS like trouble
Some problems are under your nose. You can detect them by their odor:
* The smell of burned toast-a light, sharp odor-often signals an electrical short and burning insulation. To be safe, avoid driving the vehicle until the problem is diagnosed.
* The smell of rotten eggs-a continuous burning-sulphur smell-usually indicates a problem in the catalytic converter or other emission control device. Don't delay diagnosis and repair.
* A thick, acrid odor usually means burning oil. Look for sign of a leak.
* The smell of gasoline vapors after a failed start may mean you've flooded the engine. Wait a few minutes before trying again. If the odor persists, suspect a leak in the fuel system-a potentially dangerous problem that needs immediate attention.
* A burning resin or acrid chemical odor may signal overheated brakes or clutch. Make sure the parking brake isn't engaged. After repeated hard-braking on mountain roads, stop and let the brakes cool. Light smoke coming from a wheel indicates a stuck brake; if that happens, call the tow truck.
* A sweet, steamy odor indicates a coolant leak. If the temperature gauge or warning light doesn't indicate overheating, drive carefully to the nearest service station, keeping an eye on your gauges. If the odor is accompanied by a hot, metallic scent and steam from under the hood, your engine has overheated. Pull over immediately to avoid severe engine damage, and call the tow truck.
SOUNDS like trouble
The following squeaks, squeals, and other sounds offer valuable clues about problems and maintenance needs.
* Squeal (a shrill, sharp noise, usually related to engine speed):
- Loose or worn power steering, fan, or air-conditioning belt.
* Click (a slight, sharp noise, related to either engine speed or vehicle speed):
- Loose wheel cover.
- Loose or bent fan blade.
- Stuck valve lifter or low engine oil.
* Screech (a high-pitched, piercing metallic sound that usually occurs when the vehicle's in motion):
- Caused by brake wear indicators; signals the need for maintenance.
* Rumble (a low-pitched, rhythmic sound):
- Defective exhaust pipe, converter, or muffler.
- Worn universal joint or other drive-line component.
* Ping (a high-pitched, metallic tapping sound, related to engine speed):
- Typically caused by using gas with a lower octane rating than recommended. Check your owner's manual for the proper octane rating. If the problem persists, engine ignition timing could be at fault.
* Heavy knock (a rhythmic, pounding sound):
- Worn crankshaft or connecting rod bearings.
- Loose transmission torque converter.
* Clunk (a random, thumping sound):
- Loose shock absorber or other suspension component.
- Loose exhaust pipe or muffler.
FEELS like trouble
Difficult handling, a rough ride, vibration, and poor performance almost always indicate a problem.
* Steering:
- Misaligned front wheels or worn steering components, such as the idler or ball joint, can cause wandering or difficulty steering in a straight line.
- Pulling to the left or right can be caused by underinflated tires-or a damaged or misaligned front end.
* Ride and handling:
- Worn shock absorbers or other suspension components (or improper tire inflation) can contribute to poor cornering.
- Shock absorbers or struts due for replacement can be the culprits.
- Springs don't normally wear out or need to be replaced unless one corner of the car is lower than the others. Avoid overloading your vehicle so you don't damage the springs.
- Unbalanced or improperly balanced tires cause vibrations and may wear steering and suspension components prematurely.
* Brakes: Schedule diagnosis and repair if the "Brake" light on the instrument panel is lit or:
- the vehicle pulls to one side when you apply the brakes
- the brake pedal sinks down when you maintain pressure
- you hear or feel scraping or grinding during braking.
* Engine: Get a diagnosis and schedule the repair if the "Check engine" light on the dashboard is lit, the engine keeps running after you remove the key, or you have:
- difficulty starting the engine
- rough idling or stalling
- poor acceleration
- poor fuel economy
- excessive oil use (more than 1 quart between changes).
* Transmission: Poor transmission performance may come from actual component failure or a disconnected hose or plugged filter. Have the technician check the simple items first; transmission repairs are expensive. Some common symptoms of transmission problems are:
- abrupt or hard shifts between gears
- a delayed or no response when shifting from neutral to drive or reverse
- failure to shift during normal acceleration
- slippage during acceleration (the engine speeds up, but the vehicle doesn't respond).
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