Does a check-engine light really mean something is wrong with your engine? An OBD2 scanner can tell you. What you should do if your idiot light comes on.

The check engine light is your car’s way of alerting you that something's amiss — but it could be as minor as a loose gas cap, or more serious, like a faulty oxygen sensor. Repair costs for ...

Check engine light limits the optimum vehicle performance. In simple terms, when a check engine is detected, the vehicle adapts to a limp home mode.