heeeeeeeeeeeeeeelp 95 blazer fuel pump

[perronegro]

my step daughter has a 95 Blazer that was stalling. I tried to check the fuel pressure and it completely died. I replaced the fuel pump and it started right up but it was running rough. The fuel pressure was 44 and it wasn't dropping with the car running. I took it to Pep Boys and it died again. I had them check it and they replaced the fule pump again. After I picked it up from PB it was running fine but the very next day it started to stall again. PB told me that someone was messing around with the wires inside the glove box which I believe are the relays for the fuel pump. I switched the relays and it seemed to work fine for a day. I replaced the old relays with new ones and soon after the car totally died again. I believe it is the fuel pump (again). Is there something making the fuel pump break? Is it related to the relays or is it the fuel regulator? How many times do I have to replace the fuel pump? Can someone help? Thanks.

[BlazerLT]

Fuel pressure is too low.

It should be 56-64psi with the key at the first position before start and max 10psi lower when running.

[ricksza]

The pressure should hold steady with the engine off. The rough running could be caused by many things such as injector, regulator or EGR valve.

[Rockonafly]

My 92 jimmy 4.3L CPI was doing a similiar actions. What I saw was at the first position, fuel pump running, pressure was at 58 psi. As soon as the pump stopped the pressure bled off quickly. With the engine running, pressure was at 50 psi and constant since the pump was running. I found a 1/4 inch hairline crack in both the supply and return line under the air intake plenum. Also I replaced the fuel injector while I was there (it had 130k miles on it). Problem fixed. After pressure: key in first position - 60 psi and steady. Engine running - 52 psi and steady. This is the original fuel pump that came with the jimmy.
I would evaluate your pressures before going after the pump again. I think there is more than one problem here but I would evaluate fuel first. I hope this is helpful.

[chcknugget]

At least the injector and nut kit is easier to replace than a fuel pump... Costly, but easier.

[perronegro]

Originally Posted by chcknugget

At least the injector and nut kit is easier to replace than a fuel pump... Costly, but easier.

i cant check the fuel pressure because there is none 0 nada but i dont want to change anohter fuel pump if something also is wrong and making the pump go bad

[ricksza]

Do you hear the pump run? Does the relay click for the two second prime?