Steady or flashing check engine light? What the most common causes are, when it is safe to keep driving and how professional diagnostics help.
Steady vs. flashing
A steady light means the engine computer found a problem that should be checked soon. A flashing light means an active misfire that can overheat and ruin the catalytic converter. Slow down and get it checked right away.
Common causes
Loose gas caps, failing oxygen sensors, worn spark plugs or ignition coils, vacuum leaks, mass airflow sensor problems and catalytic converter issues are the most frequent causes.
Why the code is not the answer
A trouble code tells you which system reported a fault, not which part failed. A P0171 "lean" code, for example, can be a vacuum leak, a dirty sensor or a weak fuel pump. Proper diagnostics test the parts involved before anything is replaced.
What to do
Check that your gas cap is tight. If the light stays on, flashes, or the car runs poorly, schedule a diagnostic. Brake Kingdom uses professional scan tools and testing to find the real cause on all makes and models.