1997 GMC Jimmy Not something you normally get.

Okay, so I have this 97 GMC Jimmy SLT V6 vortec. I had the engine replaced 1,000 miles ago and I just had an inspection done (new york state) It had failed twice for emissions ALL SENSORS SAID NOT READY both times. I put 1,000 miles into this truck so I knew some should have worked. Now this is when it becomes a head scratcher. I used a personal scanner and monitored the sensors as I drove the vehicle and the sensors worked! I went back to the local inspection shop and then the emissions failed again. I then started up the truck and looked on my personal scanner and then they worked so I had them inspect it while the engine it was running. It passed the NYS emissions test. So from what it seems like everytime the key shuts off, the computer resets almost like I disconnect the battery from the vehicle. Also note that it runs and starts perfectly fine. Its just that every morning the computers "fuzzy logic" has to re- adjust (rpms balance out) then it will be fine until next time I start it. All connections are on very well I know this cause I checked myself and so did mechanics but noone can figure it out. My only diagnosis at this time is that the computer forgets its logic almost like it loses power from the battery