fuel pressure problem

[chevyz28r]

Hello,

I have a 93 Lumina Z34 3.4 auto. Its been a great car!!
I lost the fuel pump a few months back, I changed it , and its been fine for about 2 months. then it started to whine, still ran, so I got them to give me a new one. When I pulled the old one out there was glay like dirt all around the screen (yes it was new), I cleaned the whole tank out. I changed that one, now it pits and sputters........I checked the fuel pressure and it was up to 60 lbs. Thinking the fuel pressure regulator was bad now, I changed that also. still doesn't help ??? When i turn the key on, the pressure goes up to 80 lbs.......when the pump stops......it goes back down to 40. when i try to start it it shoots back up to 70-80 lbs again???? I am checkin the pressure before the regulator.

__________________
thanks
Jeff

[TheProfessor]

have you checked the fuel return line

[chevyz28r]

Pressure wise.....didn't see a way to check on the return. I want to blow out the return line but don't have the part to take the line off with. I DID take off the return line where it goes into the tank....and fuel does flow out......but not sure how much.

[chevyz28r]

Pressure wise.....didn't see a way to check on the return. I want to blow out the return line but don't have the part to take the line off with. I DID take off the return line where it goes into the tank....and fuel does flow out......but not sure how much.

[TheProfessor]

hmm do you have a stock pump

[chevyz28r]

yes