Check engine light: can I drive, and what should I check?
A quick decision guide for a steady or flashing engine light, with safe checks and the information to take to a garage.
1. Decide whether to stop
If the light flashes, the engine shakes badly, power drops sharply, or you smell fuel: pull over safely, switch off and arrange assistance. A misfire can damage the catalytic converter.
A steady light alone is not permission to keep driving. Check the handbook; stop if there is overheating, an oil-pressure warning or unusual noise. If the car runs normally, arrange a prompt diagnosis and avoid hard acceleration.
2. Save the evidence before clearing anything
Record the exact code, whether it is pending or confirmed, and the freeze-frame data. Note the engine temperature, speed and when the light first appeared.
If the light started after refuelling, check the fuel cap seal and close it as instructed. Not every vehicle has a conventional cap.
3. Ask for a test, not just a part
Enter the code with the make, model, year and engine. A code identifies a condition or circuit, not necessarily a failed component. Ask the garage which test confirms its diagnosis.