having a hard time decifering what your setup was and what it is now.

did you have a y8 auto motor w/ y8 auto before?

are you y8 5 speed motor w/ y8 auto ecu now with the y8 auto throttle body?

list your setup like this so i know exactly what your combination of engine, ecu, throttlebody, iacv is now.

when you said you changed the harness do you mean you changed out the entire engine to ecu harness, or just the portion of the harness that was the 3 wire plug?