starting problems

I just put a new fuel pump and fuel filter in 2000 4.3l bravada and now it won't stay started. I'm sure I hear the pump turn on and off. It will start running at high rpm for a second or two then will start sputtering then shut off. Will start right up but will sputter then die, if press on gas pedal will stay running. When I manually held the throttle open, after many attempts to start, there was smoke. I sure could use some ideas it's been a week!

It likely needs to be scanned so the computer can help diagnose the problem.