i Just instlled a new fuel pump in my 98 2 dr tahoe and when you hook a pressure tester to it and press the button to allow the fuel to flow out the hose it cuts out my dad has the same engine and it doesnot cutout when he allows the fuel to flow it out what could this? the only difference is that my new pump came with a new connector but it was wired to the factory schematic. also my fuel guage jumps back and forth rapidly and does more so when the a/c is on what could this be?

 

how much pressure ya got?
is it an o-really's or autozone pump?

hope its not a Carter