I have a Chevy Silverado 4.3 v6. I just put a tranny in it, drove it 3 time, backed it in to my drive way, and now it will fire but shut right down. I have replaced the fuel pump, fuel filter, fuel pump relay and still nothing. It had a aftermarket alarm in it, well I took that out, and still the same thing. Changed the battery still nothing.i have seen videos on YouTube of trucks doing the same thing, but no one seems to know why. Dose anyone have any idea what this could be?

 

Have you checked the ignition?

 

i m a boat mechanic, so working on cars is a little new to me. How do I check it

 

Sounds like it could be the idle control valve