A few months ago my check engine light came on. Scanned it and it was secondary air injection failure. Took it to a shop and told me it was fine so I cleared the light. Didnt come back. About a month ago, the light came on again. Checked it and it was a misfire. Had the car checked out and again it was fine. Cleared the light. I figured no big deal, both of those were probably just random instances.
About two weeks ago, light came on again. Next day I started it up to go have it scanned and the light was gone. Sure its a relief its gone, but I'd like to at least know what code is was throwing. Last week, same thing again. Light came on, and about an hour later it turned off. Again yesterday. Light came on and turned off within 24 hours.
Maybe I've misunderstood in the past, but isnt the car supposed to hold codes UNTIL they are cleared? I dont understand whats resetting the codes. I'm not having any battery problems, so I dont get what could be clearing them.
I'm starting the think its the computer going out on me. The car runs normal before, during, and after the light comes on, nothing changes. No problems.
Any suggestions? Is there a way to check the computer to see if its going bad?
2000 Lumina, 3.1 engine. 145k