Ok lets see... I changed the engine in my Camaro. Bought it from Evergreen as an OEM spec engine. All senors and gauges APPEAR to be connected and functioning. Check engine light comes on... check codes and all I get is 23 low MAT temp. The engine is behaving oddly. I had to set the idle to 2000RPM to get it to stay running at idle... then it will die down to 750-500 rpms... kinda sputter then pop back up to 2000RPM. I do not think the 23 EC is the WHOLE problem as I had this code on the old engine and it did not do this. So I guess I need some advice on where to check. No vacuum leaks that I can find, seems to get fuel good as it runs great when I'm going places, just not when i'm sitting there. I'm looking in to getting an OBD-I scanner for a pc and integrating a pc in to the car for live data all the time. I would just get a scanner but this will help with multi-media in the car too

 

You running MAP or MAF?

 

it is not speed density so that is MAF right?