I spun a barring in my 94 z28. I purchased a motor (5.7) out of a 96 caprice(Iron Heads). I put the motor in and it will crank but not start (no fuel pump power or opti power) (both opti and fuel pump new). The computer is the original 94 z28 (OBD1) and harness too.(96 OBD2). Please Help!

 

wait im confused, u said original pcm from z28 OBDI and harness from the impala OBDII? I dont think that will work if thats what youre saying. You should have stuck with the original harness from the car. Also, i believe you need to swap the knock sensor cause obdII sensor is a different frequency or bs. Did you remember to connect all yer plugs under the dash in the passenger kick panel? I believe theres 4.

 

Use your 94 engine harness and connect the opti harness from the 96 to it. Use your original knock sensor as mentioned above.