When the check engine light comes on, it means that there is a problem with your cars engine or emissions system. The reasons for the light turning on can range from something minor like a loose gas cap to something more serious like a faulty catalytic converter. The light could be a minor issue, such as a faulty gas cap, or it could mean something more serious, such as a misfiring engine. If the light begins flashing, it indicates a more serious problem, such as a misfire that can quickly overheat the catalytic converter.

When the check engine light comes on, your cars computer stores the corresponding diagnostic trouble code (DTC) in its memory. It can be hard to figure out what the problem is, so its best to have the vehicle checked by a mechanic. CarMD, an automotive telematics company, publishes an annual Vehicle Health Index that compiles the 10 most common check engine codes, along with their estimated cost of repair.

Here are some tips on what you should do when the check engine light comes on:

• Look for a serious problem that requires immediate attention. Check your dashboard gauges and lights for indications of low oil pressure or overheating. These conditions mean you should pull over and shut off the engine as soon as you can find a safe place to do so. On some cars, a yellow check engine light means investigate the problem and a red one means stop right now.
• Reduce speed and load. If the check engine light is blinking or you notice any serious issues with your cars performance, reduce your speed and try to reduce the load on the engine.
• Get the vehicle checked by a mechanic. If the check engine light is on, its best to have the vehicle checked by a mechanic as soon as possible. They can diagnose the problem and recommend the necessary repairs.

Ignoring the check engine light can lead to more serious problems and costly repairs down the line, so its important to address the issue as soon as possible.