all of the warning lights that might light up on your dash, nothing
strikes fear in the hearts of motorists more than the "check
engine" , or "service engine soon" light.
But do you know what? Even though "check engine" sounds expensive, it might be something very simple causing the light to come on. Let me explain how the system works.
Your car has a computer that runs the engine and many other systems on your car. There are many sensors placed throughout the engine that constantly send information to the computer. The computer knows exactly what the normal readings should be from each of these sensors, and if any of them send a reading that is not normal, the computer will set a code, and turn on the check engine light. If the computer considers it a big problem, the light will flash off and on as you drive. That is a warning telling you that you should take it real easy with the car, and get an appointment made ASAP to have it checked.
If the light is not flashing, it usually does not mean that you need to pull over and stop the car. Just take it easy, and you should be fine to continue driving.
The mechanic will hook up a diagnostic scanner to the car, and it will tell him what code was stored in the computer. But this is not a magic box that tells him what is wrong. It only gives him an idea of the affected area, and he needs to do some diagnostic work from there. What might start out as a misfire code could turn out to be any of a number of things like spark plugs, or a sensor of some kind. You just don't know until you go through some steps and run the problem down.
Sometimes the problem can be surprisingly easy. Believe it or not, the fuel system even has sensors associated with it, and one very common reason the check engine light comes on is if you don't tighten the gas cap enough. So if your check engine light ever comes on after you filled up with gas, try tightening that cap before you go through the expense of having a mechanic look at it. It might save you some money.
The Auto Guy – Jim Champion
Charlie Graham Body and Service
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