What makes an engine light keep coming on when the car has been checked and rechecked?

Question by mswnana: What makes an engine light keep coming on when the car has been checked and rechecked?

My daughter took her car to the shop because the engine light kept coming on. They said there was a hole in something and that it was fixed. She drove about 10 miles and it came back on. She needs to get it inspected soon. Does anyone know anything about this, please?
It is a 1999 Mazda. My daughter already took it to the Auto Zone place, they put it on the thing and said it was one of two things. One of the two things was fixed (a hole in something), my daughter drove it off, and the light came back on immediately.




Best answer:

Answer by bobweb
The best place to take that problem is the car dealers because they already know what recalls and technical service bulletins may lead to that problem. Why pay an independent garage to "get smart" about a unique problem to your make year model vehicle? Who's trained to work on your make year model vehicle? Answer: The dealer's technicians. In addition, the car dealer technicians have access to manufacturer unique computer trouble codes and PCM reprogramming.

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