I have a 2004 STI engine that Im getting ready to drop into my 2007 STI. Failed warranty and its a low mileage motor. My question is will my 2007 ECU run this 04 motor. i know the smog pump stuff is different and it may pop an emissions code. But i have heard that the newer ecu will run it, everything seems to be the same. Just need to get some guidance on this one.

 

07 ecu has a bad factory tune. I would flash for the 04 setup if i were you

 

Assuming your still running the 07 manifold and injectors the ECU will run it but I would suggest having it tuned.

Mike