When your car's "Check Engine" light comes on, it's usually accompanied by a sinking feeling in the pit of your stomach. The light could mean a costly problem, like a bad catalytic converter, or it could be something minor, like a loose gas cap. But in many cases, it means at minimum that you'll be visiting your mechanic to locate the malfunction and get the light turned off.
The Check Engine light, more formally known as the Malfunction Indicator Lamp (MIL), is a signal from the car's engine computer that something is wrong. Older vehicles may not have this, but any newer vehicle is equipped with a tiny all-knowing computer that will be your lifeline in communicating any problem with how the engine is running. Your Tire and Automotive service department can diagnose the problem, but there are ways to preview what the problem might be.
Prior to 1996, carmakers had their own engine diagnostic systems, primarily to ensure their cars w ...[more]