99 gtp starts and dies..

[2004pontiac]

Hello, we had a 99 gtp towed in today, just died. Any way it will start and die, start and die unles we give it throtle. First we noticed the SC belt and idler pully was gone. But customer said its been running like that. So we did a fuel psi text. with key on gauge shows 55psi, Then when it fires up drops to approx 45 then the gauge drops stedly to zero and dies at approx 15psi. Humm so we did the cheap changed filter, no good same reading, checked psi reg seemed ok but we changed it, same readings.. so humm fuel pump thats all thats left right.. so we had a good one. Changed it over and still same syptoms, 55 with key on then 45 under crank, then when it start the psi stedly drops to zero.. car dies. not if i chasing my tail,barking up wrong tree or what.. any ideas?

Thanks

BTW the iac,tp,map and mas have been changed.. with no change.. its like the fuel pump stops.. we also changed the relay..

[BlackGT97]

same thing i said on other thread.....try to only post in one area. mods will delete one of these probably.

[nicks98gtp]

possibly the fuel pump resistor went out? Mine had the same symptoms when mine went, the car just died while driving, then it would restart, stutter and die after a few seconds without throttle keeping it alive.