help: check engine light
 

engine runs after rebuild .. with pfc it idles at 2.5k rpms .. so i threw in the oem ecu and car started to idle at 1.5k rpm .. not too bad .. but then i let it idle for about 7 mins and come back out to check on it and its idling at 2k rpm and the check engine light comes on .. is this a sign of something more problematic?

also my knock sensor wire looks iffy and my oil level sensor wire is severed, could it just be the oem ecu is not seeing these and giving me the check engine light?

thanks mahjik