The Lemon IndexCar symptoms: what that shake, noise or smell usually means.
Pick what your car is doing. Each page gives the common causes, how serious it is, and the models and years owners report it on most, from 1,632,668 complaints to the U.S. government.
Find your symptom
Brakes
Brakes not workingOften: a brake fluid leak or a burst brake line29,505 complaintsABS light onOften: a dirty or failed wheel speed sensor19,928 complaintsBrake pedal goes to the floorOften: a brake fluid leak (lines, hoses, calipers or wheel cylinders)13,417 complaintsCar shakes when brakingOften: warped or unevenly worn brake rotors10,248 complaintsSqueaky brakesOften: pads near the end of their life (a metal tab squeals on purpose)3,629 complaintsGrinding noise when brakingOften: brake pads worn down to the backing plate3,595 complaintsCar brakes by itselfOften: automatic emergency braking reacting to shadows, bridges or signs2,857 complaintsBrake pedal hard to pushOften: a failing brake booster2,265 complaintsCar pulls to one side when brakingOften: a sticking or seized caliper1,481 complaintsSteering and suspension
Steering wheel hard to turnOften: a fault in electric power steering (motor, sensor or software)42,163 complaintsCar shakes at highway speedOften: wheels out of balance12,075 complaintsSteering wheel locked upOften: a failed electric steering motor or control unit10,461 complaintsCar pulls to one sideOften: wheel alignment out of spec5,097 complaintsDeath wobbleOften: a worn track bar or track bar bushings4,793 complaintsClicking noise when turningOften: a worn outer CV joint (often after its rubber boot tears)4,010 complaintsTire pressure light onOften: a tire that is low on air, often from a nail or a leaking valve3,826 complaintsUneven tire wearOften: wheel alignment out of spec2,896 complaintsLoose steering wheelOften: worn tie rod ends2,819 complaintsHumming noise while drivingOften: a worn wheel bearing2,435 complaintsClunking noise over bumpsOften: worn sway bar links or bushings703 complaintsEngine
Car loses power while drivingOften: limp mode set by the engine or transmission computer to protect itself60,729 complaintsCar won't startOften: a weak or dead battery41,831 complaintsCar stalls while drivingOften: a failing fuel pump or fuel pressure problem41,546 complaintsCar accelerates by itselfOften: a floor mat or object trapping the accelerator pedal19,477 complaintsCar hesitates when acceleratingOften: a dirty throttle body or mass air flow sensor19,114 complaintsEngine overheatingOften: low coolant from a leak18,047 complaintsGas smell in carOften: a leaking fuel line or fuel injector15,361 complaintsOil leakOften: a leaking valve cover gasket12,481 complaintsCar burning oilOften: worn or stuck piston rings11,356 complaintsCoolant leakOften: a leaking radiator or hose10,816 complaintsEngine knocking or tickingOften: low engine oil or low oil pressure9,685 complaintsEngine misfireOften: worn spark plugs9,466 complaintsBurning smell from car or engineOften: oil leaking onto the exhaust9,275 complaintsCar stalls at stop or idleOften: a dirty throttle body or idle air control valve8,914 complaintsSmoke from under the hoodOften: oil leaking onto the exhaust7,209 complaintsCar jerks when acceleratingOften: worn spark plugs or a failing ignition coil7,068 complaintsCar shaking and check engine light onOften: a misfire from worn spark plugs or a failing coil6,375 complaintsRPM goes up and downOften: a vacuum leak5,352 complaintsCar shakes at idleOften: worn spark plugs or a failing ignition coil5,270 complaintsEngine sputteringOften: a clogged fuel filter or weak fuel pump4,763 complaintsCar shakes when acceleratingOften: worn inner CV joints4,496 complaintsCheck engine light flashingOften: an engine misfire (spark plugs, coils or injectors)3,859 complaintsExhaust smell inside carOften: a leak in the exhaust manifold or pipes2,298 complaintsWhite smoke from exhaustOften: a blown head gasket1,687 complaintsEngine cranks but won't startOften: a failed fuel pump or fuel pump relay627 complaintsCar won't start, just clicksOften: a weak or dead battery468 complaintsTransmission
Transmission slippingOften: low or burnt transmission fluid12,978 complaintsCar won't go into gearOften: low transmission fluid12,236 complaintsTransmission shifting hardOften: low or old transmission fluid10,913 complaintsTransmission shudderOften: torque converter clutch shudder4,768 complaintsCar rolled away in parkOften: a shifter that isn’t fully in Park3,069 complaintsWhining noise when acceleratingOften: low transmission fluid or a worn transmission (CVTs often whine as they wear)1,674 complaintsClutch pedal stuck to the floorOften: a leaking clutch master or slave cylinder1,006 complaintsElectrical
Airbag light onOften: a faulty seat belt buckle or seat sensor41,694 complaintsHeadlights not workingOften: burned-out bulbs18,955 complaintsSpeedometer not workingOften: a failed vehicle speed sensor or wheel speed sensor10,987 complaintsCar door won't openOften: a broken inside or outside handle10,886 complaintsCar battery keeps dyingOften: an old or failing battery9,848 complaintsPower window not workingOften: a broken window regulator (cable or plastic clips)8,499 complaintsAll dashboard warning lights onOften: a failing alternator or weak battery (low voltage)7,423 complaintsBackup camera not workingOften: a damaged camera wiring harness (often in the tailgate or trunk lid)5,462 complaintsTouchscreen freezing or going blackOften: software that needs an update3,077 complaintsHeating, AC and body
Fuel gauge not workingOften: a worn fuel level sending unit6,442 complaintsSunroof shatteredOften: a flaw in the glass from manufacturing6,382 complaintsCar heater not workingOften: low coolant from a leak3,819 complaintsWater leaking inside carOften: clogged sunroof drain tubes3,047 complaintsAC blowing warm airOften: a refrigerant leak (often the condenser or a line)2,971 complaintsMold or musty smell in carOften: mold on the AC evaporator1,052 complaintsNo symptom in this list matches. Try one word, like shake or leak.
The dot is how serious it usually is: yellow get it checked, orange fix soon, red stop and get help.
Got a warning light with a code?
If the check engine light is on, the code tells a shop where to look. Look up any engine code →
Quick answers
What is the most common car symptom in complaints?
Among the symptoms we track, owners describe car loses power while driving most (60,729 complaints), then steering wheel hard to turn and car won't start.
Which symptoms mean I should stop driving?
Brakes that fail or a pedal that sinks, steering that locks or goes heavy, overheating, smoke, a fuel smell, a flashing check engine light, a car that stalls or speeds up on its own, and exhaust fumes inside the car. Pull over safely and get help.
Is a symptom proof that my car is defective?
No. These pages count owner complaints to NHTSA. They show which model years owners report a symptom on, not what is wrong with any one car. A shop has to diagnose your car.
How we count: we matched owners' own wording in NHTSA complaint text (for example “shakes when braking”), then read samples of each match to check them. A complaint can describe several symptoms. Pages with fewer than 200 matching complaints stay out of search results. General information, not repair advice for your car.
Updated · Free to use with credit: Source: The Lemon Index (lemonindex.com)
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