i have a gsr swap in my car and just added a victor x manifold and i start the car and it revs up automatically and stays t 3.5k.

i checked all vaccum.

i have a p73 ecu and r176 looked burned outttt or the little black thing next to it.

 

How did you "check all vacuum?" 3500 RPM cannot be sustained by the amount of air and pressure that should be getting in through normal idle channels. Extra air must be entering the manifold from somewhere.

 

found! intake manifold gsket