I have a 97 Grand Prix GT with the 3800. I put a salvage yard motor in from an 01 Bonneville. I had to change brackets and stuff and all that went fine. I went to fire it up and as soon as you fire it up and shut it off two or three times it fouls out the plugs. I have correct amount of fuel pressure and good spark everywhere but it still will not start after two times of starting and than shutting off. Need fixed asap!!! Please any suggestions post up and reply. THANKS JAKE