just replaced the fuel pump. is it possible that my truck is letting too much fuel return? when the pump kicks on it sounds like air under the hood. or water flowing. i dont have a pressure gauge, but it seems to have a lot more pressure than before. but it wont run. like it isnt getting gas. im thinking maybe its returning all the fuel. cause it sounds like air or water or something under the hood, but nothing is leaking. it only makes the sound when the fuel pump is on.

 

Could be. Disconnect the vacuum line to the fuel pressure regulator and see if you have gas in there. Get a vacuum pump and see if it will hold vacuum while you're there. Any codes?

 

no codes. no gas in the vac line. and i have no way of checking vac pressure.