So you have owned your car for a while, and a pesky Check Engine light has appeared on your dashboard. Or, maybe you are just preemptively curious about what does the check engine light mean? Some cars have a check engine light that illuminates automatically at odometer intervals, so if your car has recently hit a milestone, there may actually be nothing wrong with the engine. Some other common causes of a lit check engine light are a leaky gas cap, a malfunctioning oxygen sensor, the mass airflow sensors on certain vehicle models, the catalytic converter is below efficiency levels, or potentially the spark plugs/ignition system needs work or replacement. With any vehicle, however you can take the car to a local auto parts chain (Auto Zone, Advance Auto Parts, O’Reilly’s Auto Parts, among others) and they will read the code with a special tool free of charge. They will even reset the on-board computer’s code for you – sometimes a code gets triggered when there is no actual issue, so if the light doesn’t come back on after a reset, you’re probably fine and don’t need to make any repairs.
What if I fixed the problem already, but the Check Engine light is still on?
Make sure that the mechanic who performed the repair reset the on-board computer and wiped the code on the check engine light. If they do not, the problem may be fixed but the light will still stay on until reset. If it stays on after a reset, double check to make sure it is not outputting a different code. If it is still outputting the same exact code after a reset, then either the part that was replaced is also malfunctioning, or another part is causing the actual malfunction in the engine. Refer to a mechanic or check the vehicle manual for potential candidates as to what could be wrong with the car. You can also use Google to utilize the experience of other owners of the same type of engine, forum boards in particular can be quite helpful in these situations. Good luck with your car!