Like the title says service engine light came on then went off like 48hrs later. Let me give you some history and maybe some of you can help me out.

2 weekends ago I had my 2500 dacco stall converter install in my tranny, everything works fine, no problems at all with the stall and the truck is most definitely more fun to drive. The Thursday after I had it installed,my wife and I move from Tulsa to Santa Fe, NM. Everything was going well till I got to Amarillo, TX and stopped at a DQ to get some icecream. After I left DQ I started the truck and it was indling rough and the SERVICE ENGINE SOON light come on. I continued about my trip and the truck was running fine and pulled 17.7mpg. The next day I went out and started the truck and the stupid light was still on, so my father-in-law and I went to O'Reilly's and as soon as pulled into the parking lot it went OFF!!!

Any explaination as to what might have been going on? At the time I thought maybe a plug fowled out, spark plug wire melted, or an O2 sensor went out.

 

Without the code it will be hard for anyone to give you any real solid ideas what it could have been. The code, however, should be still stored in the PCM as a history code for up to 40 ignition cycles. It could come back again if the PCM detects a fail condition for the code stored in history.

I would assume since the light went off in the parking lot, you didn't have them attempt to read codes. If you didn't, try taking it in and have them read for codes anyway and see if it brings up the codes stored in history or pending.

 

Could have been a random misfire caused by the stall. i know some converters will cause a false misfire due to different rotating mass than the stock converter.....but that is usually in the 9.5 converters.

 

Maybe that was it I don't know. The truck is running great now.

 

even if the light turns off it still stores the code. You should be able to pull it with a code reader. With out knowing the code it could be any thing....