If the “check engine” marker in your vehicle lights up, don’t panic – although it could be a warning of a major problem, it could also be as simple as a worn spark plug. A check engine light is designed to turn on whenever any problem – and we mean ANY problem – with an engine is detected. Before assuming that you’re looking at a significant and costly repair, check a few minor things.
One common cause of a check engine marker light-up is spark plug wires gone bad. As a spark plug ages, its wires begin to develop tiny cracks that can allows bursts of electricity to escape rather than traveling from the spark plug’s tip to the electrode. This can cause your engine to misfire and trip your check engine light. With your engine off, remove your spark plugs and check the wires for tiny cracks or holes, particularly near the ends of the wires. If you notice any cracks or holes, or if the spark plugs simply look worn, it may be time to replace them.
Also check your hood for the possibility that rainwater or water from car washing could be leaking into it. Water that drips onto a spark plug wire and runs down to the engine’s head can cause a short and, again, trigger the check engine light. This happens often with overzealous car owners who spray down their engines with high-pressure hoses or fail to cover and protect critical engine parts.
Another simple solution may be to tighten your gas cap. Some cars measure pressure inside your gas tank via a series of mathematical algorithms that involve factors such as your driving style. If the pressure strays from its average, your car thinks something is amiss and alerts you via your check engine light. All that’s amiss, however, may be a loose gas cap.
If your check engine light comes on, we suggest taking your vehicle to a local repair shop and asking for a diagnostic test. You also can purchase car engine diagnostic tools that can read and deliver a car engine’s trouble codes. These do-it-yourself diagnostic code readers work via the OBD-II port beneath your vehicle’s hood and are available at auto parts stores and online.