Why is my check engine light on?
The check engine light has more to do with your vehicle's on-board computer system than your engine. When the light is on, the computer system is telling you there is a problem.
The problem may had to do with fuel, electrical, ignition, engine, or even pollution.
You should always have a trained technician test your on-board computer when the check engine light comes on, even if you don't experience any obvious problems.