I have a edelbrock performer 750cfm (manual choke). I let the motor warm up and still no luck. When you say check for a vaccum leak, where are you referring to check? (around the intake)?? I did mess with the air/fuel ratio while the motor was in the other truck, when it was in the other truck it was hooked to a 5 speed. Would this make a difference in auto?? How about having a stall converter and I have a stock motor would that make a difference. thanks for the reply's keep em coming