my 96 tahoe has a performance issue at 3000 to ? rpm. fuel pressure is at 50 psi while idleing and 60 undr a load. i rebuilt the motor do to a spun rod bearing, new regulator, tps, and i replaced the fule pump w/ a acdelco pump and the truck would not start! i checked psi and it only had 45psi. so naturaly i assumed it was bad, so i purchased another one, same problem! i put in the original one and the truck runs.??? i checked the acdelco parts list and w/ my vin, its the right part. any one else have this problem? i heard about bad pumps made in mexico, any1 have a clue? thanks. note:i had this issue before rebuilding the motor.
now that ive dissconnected the cats, it decide to stop running completly and all elect. turns out fine, replaced spider, still wont start. i am also still looking for a chevy pos guru,

 

i found the problem w/ everything above finally! I replaced the pump, but not the basket, what a jack ***, thats what i get for short changeing it. Well, next time maybe u guys will have an insight on my next problem.

 

Happy to hear you solved your problem...whats the "basket"? My 00 Hoe Limited is acting stupid and I have been chasing a hard start problem that I believe is the fuel pump check valve going bad.