Today, most cars are controlled by computers. The fuel injectors, the spark plugs, the steering system and more are all told when to fire and when to move by an on board computer system. If something’s going wrong with your car or engine, your on board computer can tell you about it. If the computer senses something is wrong with one of your car’s systems, it will turn on a dashboard light, like “ABS Brakes” or something less specific, like “Check Engine.” Some people try to disregard their Check Engine light. And some have even gone as far as disabling it and that could be a costly move.