1993 b2600i too much gas

I need help bad, I have a 93 b2600i pu. I have had the engine rebuilt from top to bottom, all new parts, started it up ran fine shut it off and would not start back up. It appears to be shooting too much gas up to the injectors making it flud out before it starts. If you pinch the gas line it will start but run rich and idle a little high, black smoke out of the exhaust. Had it put on the machine was told it was the ECM. sent that off to CA. had rebuilt, put back in, no change..Please help what could this problem be.. Too much money invested to stop now...

If you pinch the fuel line it runs but does not idle well.... Try putting a fuel regulator in line some where. You can get an adjustable regulator that will control how much fuel gets to the engine. Where is your fuel pump? Did it get changed during rebuild? Just a thought.

you need a computer