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Troubleshooting and optimum performance tune – ups :
Whether you have a trusted technician who works on your vehicles or you prefer to do the work
yourself, ACDelco wants to help you keep your cars and trucks running strong, long and
efficiently. Use the links below to identify car noises, smells and leaks, as well as access
frequently asked questions about car care and performance problems.
Car Noises
What’s your vehicle trying to tell you when it clicks, clunks or grinds? Translating these
car noises is key for automotive technicians who are trained to identify problems via
sound. The important thing to remember is to be specific. Narrow that rattle down and
then document when it happens – details such as when the car is hot, cold, at idle, moving
at 55 mph, etc. can go a long way in helping to diagnose the problem.
Type of Car Noise and Possible problem
Squeaky brakes - Dirt in the lining of the pads or hardening of the pads and shoes
Grinding brakes - Worn pads and shoes
Metal on metal when braking - Worn-out pads
Metal on metal when encountering bumps - Worn-out shocks
Growling from air conditioner - Worn compressor
Squealing windshield wipers - Worn wiper blades
Whining from tires when turning a corner - Dry or worn-out wheel bearings
Squealing from tires when turning a corner - Tires low on air or worn
Grinding while shifting gears - Worn clutch or clutch that needs adjustment
Screeching under the hood - Loose or worn belt
Popping from engine - Dirty air filter or bad spark plugs, wires or ignition components
Scraping or buzzing from transmission - Transmission needs new fluid
Squeaking noise when shifting - Manual transmission needs lubrication
Clunking under hood when gears change - Worn joints or engine’s idle speed may be
set too high
Knocking under hood - Clogged air filter, timing off or needs higher gas octane rating