What to Do When the Check-Engine Light Comes On

6 tips

• First, tighten the gas cap until it clicks. A loose cap is one of the most common causes, and the light often clears itself after a few drives.
• Check whether the light is steady or flashing. A steady light means get it checked soon; a flashing light means a misfire. Slow down and get to a shop right away.
• Look and listen for other symptoms: rough idling, loss of power, strange noises, or a smell. Write them down. They help the technician find the problem faster.
• Get the code read. An auto parts store will often read it free, or use an OBD scanner. The code, like P0300, tells you which system is reporting the problem.
• Do not ignore it for weeks. A small problem like a bad sensor can turn into a failed catalytic converter, which costs ten times more to fix.
• If the car also overheats, loses oil pressure, or stalls, pull over safely and stop driving. Those are signs of damage happening right now. Have it towed.

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