Help - need to identify a problem

[Mracer71]

1996 Tahoe 4 dr. At first it would start and run on idle, would rev all the way up - no problem. Then once in drive, it would not rev up, hesitation and may even die. As of now it wouldn't even start - cranks just fine. Fuel pump? Fuel filter? What do you guys think? Why would fuel pump run on idle but not on drive?

 

[Mracer71]

It was a fuel pump. $400 later i am driving again. Was in hopes to pay less, but what can i say - need the wheels to turn asap so had to pay up.