Limp mode is a reduced-power strategy that can limit engine power, RPM, or shifting after a control module detects a fault. Get to a safe place if the car is overheating, has an oil-pressure warning, ...

The engine coolant temperature (ECT) sensor measures coolant temperature and sends the reading to the engine computer. Depending on the vehicle, the computer uses that signal to adjust fueling and ...

P0420 means the ECM has detected catalyst efficiency below its threshold on Bank 1. A worn catalytic converter is common, but an exhaust leak, sensor fault, or engine problem can trigger it too. Check ...

A bad injector can make one cylinder run too lean or too rich, but rough running does not prove the injector has failed. Spark plugs, coils, compression, fuel pressure, and wiring can produce the same ...

A faulty wheel speed sensor can turn on the ABS or traction-control warning and may disable related safety features. The sensor is only one possible cause. Scan the ABS module, compare live ...

A fuel induction service may help when deposits are confirmed, but the name can cover different procedures. Ask what the shop will clean and why. Rough idle or poor fuel economy alone does not prove ...

P0340 means the engine computer is not receiving a usable signal from the camshaft position sensor circuit. The sensor may have failed, but wiring, connector, timing, or crankshaft-signal problems can ...

If the red oil-pressure warning comes on while the engine is running, pull over safely and shut the engine off. Check the oil level only after stopping on level ground and following the owner’s manual ...

Unleaded 88 is E15, with up to 15% ethanol. It is approved for many 2001 and newer vehicles, but check your owner’s manual or fuel door first. It is not for older vehicles, motorcycles, boats, or lawn ...

P0496 means the EVAP system detected fuel vapor flowing when purge was not expected. A purge valve stuck open is one possible cause, but the code does not prove the valve is bad. Check related codes ...

A failed glow plug can cause hard cold starts, rough running after startup, white smoke, or a glow-plug warning. The relay, wiring, battery, or fuel system can cause similar symptoms. Scan the vehicle ...

P0507 means the engine is idling faster than the computer’s target. A vacuum leak, throttle-body issue, disconnected hose, or incomplete idle relearn can cause it. Check for recent work and intake ...