Check Engine light after loose Gascap

[walshy]

I have searched the posts so don't get on me. Is there some way to clear the CEL on a 2000 Z24 without having to get it checked at a dealer? I have read that the new obd2 (or whatever) wont erase with the battery unattached.

[MtLeCe]

Exactly how long did you leave it unattached from the battery?! Usually takes at least 20 minutes or soo. I usually do it over night whenever I do it. Could be a possibility that the trouble code just won't go away unless it was read. Also sometimes manufactures program the CEL to come on at certain milages so that you take into the dealership for servicing. We have a camry that did that and it was a '99. Hope that helps you some.....




Matt~

[GMMerlin]

Originally Posted by MtLeCe

Also sometimes manufactures program the CEL to come on at certain milages so that you take into the dealership for servicing. We have a camry that did that and it was a '99. Hope that helps you some.....




Matt~

GM does not program the SES light to come on just to get you in for servicing. If the SES light comes on, the PCM has seen a fault in the emissions system.

The only light that is on a predetermined timer (based on engine hours) is the Change OIL Soon light...if your vehicle is equipped...and your service manual has instructions on how to reset it.

[RABarrett]

If the fuel fill cap was left loose, the computer will see it as a problem with fuel tank pressurization. The code will clear by itself after 40 tests that do not duplicate the problem. Bear in mind that the computer will only test this system under certain circumstances, not every time the engine is started. The Cavalier was particularly prone to this problem for reasons I cannot account for. As a tech, I saw more Cavaliers than anything other than the Pontiac equivalent, the Sunfire. I frequently saw the tank properly pressurize at one moment and fail the same test 30 sec later. The OBD2 scanner will tell the system to self-check this system, hence the problem code. Sometimes removing and replacing a properly installed cap fixed the problem. Make sure that every time you gas up, properly replace the cap. If the light does not extinguish, it will require dealer attention. If the light illuminates on vehicles equipped with OBD2, ('96+), the gov't requires delaer intervention. Ray

[shane157]

You can clear 96-up GM codes with most code readers, if you have an Autozone near, stop by, have them put the OBD2 reader on it (will do it for free, call ahead), they should be able to clear the code, my code reader will clear codes after the 4th read automatically.