you are going to have to get the engine light turned off at a shop or dealership. Although a 'loose' gas cap might have been the initial cause of the engine light, tightening it will NOT turn off the light. There is NO gas cap tightness sensor.
A quick corse on engine lights: 1. Most of the time when engine lights come on its when the PCM (computer) has seen a 'fault' occur more than three times in a specific amount of time.
2. After a set specific amount of time after the PCM turns on the light, if the computer has not seen that 'fault' again, it will shut OFF the engine light BUT the fault code is still stored in the PCM for retieval by a tech.
3. On Mazda's there is nothing the consumer can do to turn off the engine light in the way of key cycle's or gas pedal depressions. THe two ways are scan tool (duhh!) And disconnecting the battery (but beware you will loose all of your radio stations and the PCM and TCM have to re-learn your driving habits)
So in closing, I would get you car to a shop to get the engine light checked out since your light comes on and off, this indicates that the PCM is seeing a fault occur every once and awhile.
Cosmo. Mazda Tech
Friday, May 5th, 2006 AT 6:14 AM