Help Fuel problem

I replaced the fuel pump on my 1997 Jimmy with a fuel pump for a 1998-2000 blazer/jimmy. The jimmy started great and ran for about 30 minutes then it started to surge. I stopped and got gas and it ran fine for about 15 more minutes. The jimmy will not maintain speed when this happens and will die evenually. After I wait a couple of minutes it runs fine for about 5 minutes and then I have to stop and shut off the motor.

I would appreciate any and all help with this problem. One thing that I did not hook back up was the vent line on the forward part pf the tank. it broke (nipple) and I was told by an auto parts store that it was just a vent and not nessasary to replace.

Thanks for all the help.

I'd replace that vent line, I don't know if it could be whats causing it, but its worth a shot. I know what ur talking about cause I broke mine too. its a little round black thing on the tank with a nipple on it. it twists off, like a 1/2 twist counterclockwise, and they sell it at the dealership for $20.

replaced fuel filter. Engine still looses power and shuts down after driving it a while. Any and all HELP Appreciated.

get you a fuel pressure gauge and check the pressure in the shrader valve. if the fuel pressure is fine, then the problem cant be fuel related unless you have something wrong with one of the injectors. but a bad injector like a leaking or clogged injector wont make the jimmy cut off, just run like crap. Another thing it could be is the ignition control module at the distributor. I think you can take those out and have them tested.