Diagnosing Auto Problems

Car trouble symptoms can indicate minor or major problems with your vehicle. This glossary of terms should help you identify your vehicle’s symptom and assist you when discussing your concerns with your Certified Service technician.

Auto Problems



Brake fade Stopping distance seems to increase, causing longer braking distance, similar to braking at high speeds
Low brake pedal Brake pedal must be pushed unusually far to engage brakes
Grabs Vehicle has a tendency to move right or left when brakes are applied; brakes engage suddenly when applying steady pressure to brake pedal



Cuts out Temporary complete loss of power. Engine quits at irregular intervals. May occur repeatedly or intermittently, usually under heavy acceleration.
Detonation Mild to severe pings, usually worse under acceleration. Sounds like popcorn popping.
Dieseling Engine runs after ignition switch is turned off. Runs unevenly and may make knocking noises.
Hesitation Momentary lack of response as accelerator is pressed. Can occur at any speed. Usually most severe when starting from complete stop. May cause engine to stall.
Miss Pulsation or jerking that changes with engine speed. Exhaust has a steady spitting sound at idle or low speed. Not normally felt above 30 mph.
Rough idle Engine runs unevenly at idle. Car may also shake.
Sluggish Engine delivers limited power under load or at high speed. Won't accelerate as fast as normal. Loses speed going up hills. Vehicle has less speed than normal.
Spongy Little or no increase in speed when accelerator is pushed down. Continuing to push pedal down will eventually give an increase in speed.
Stall Engine stops running or dies out. May occur at idle or while driving.
Surge Vehicle speeds up and slows down with no change on accelerator pedal. Can occur at any speed.

Steering & Handling


Bottoming Suspension moves to extreme end of travel and hits compression bumpers. Feels like a heavy thud.
Excessive play Steering wheel must be turned unusually far before vehicle responds.
Hard steering Vehicle difficult to steer, especially during parking situations or when first started.
PullsVehicle moves to one side when steering wheel is released.
Shimmy Rapid side-to-side motion of both front wheels felt in steering wheel.
Sway/pitching Mushy or spongy ride; vehicle takes a long time to recover from bumps in the road.
Vibration Vehicle shakes.
Wanders Vehicle meanders, requiring frequent steering adjustments to maintain direction.
Antifreeze or coolant leak Sweet odor, usually accompanied by steam from under the hood.
Axle leaks Black stains with heavy, thick consistency.
Burning oil Thick, heavy odor, sometimes accompanied by smoke from under the hood or from the exhaust.

Odors &


Coolant streaks Yellow, green, pink, or orange stains that are lighter and thinner than oil.
Crankcase, oil, power-steering
fluid leaks
Brownish stains
Electric short Acrid odor, like burned toast
Emission Continuous, heavy sulfur odor-like rotten eggs
Overheated brakes or clutch Burning rubber odor
Overheating Hot, metallic odor usually accompanied by antifreeze/coolant odor.
Transmission oil leaks Reddish stains