Check Engine Light
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When your check engine lights comes on, you may be torn between utter panic and just wanting to ignore it and hope it goes away. That's perfectly understandable. That same check engine light could come on for anything from a serious engine or transmission problem all the way down to a loose gas cap.
There's a very common misconception that the trouble codes stored in your engine computer when your check engine light comes on will specifically identify a problem. It's really more like pointing to the symptoms of a problem. Example: A P0171 lean condition code could be the result of low fuel pressure, vacuum leaks and unmetered air entering the engine past the air flow sensor, restricted injectors and so on.
For any given trouble code, there could be a number of causes. So your trained technician takes the trouble code as a starting point and begins a diagnostic process to determine the cause of the problem. And some problems take longer to solve than others. For example: if your vehicle is running rough, the possible causes could be a:
- Fouled or worn spark plug
- Spark plug wire
- Ignition coil
- Fuel injector
- Vacuum leak
- Low compression in the cylinder
Or an electrical problem with a wire or the engine control module may have a faulty circuit board. This does take time to connect test equipment and diagnose the condition to determine the correct repairs needed.
When your engine management system logs a problem and illuminates the check engine light, your service technician will plug in a scanner, download the trouble codes and go to work tracing the cause of the problem.
That's just the first step. That's when your technician's training, equipment, databases and skill get put to work diagnosing the problem and fixing it.
If your check engine light is flashing it means that the problem could lead to serious damage. You should get to the service center as soon as possible to get the problem solved.
For an interactive video on your check engine lamp, click here.