Fuel Pump

**1998 T/A** · 09-25-2008, 01:58 PM

is there anything you have to do after installing a new fuel pump and filter?? i've been through 3 already and they are GM fuel pumps not 100 dollar autozone pumps. the GM is under warranty but 3 pumps in 4 months????

**Orcus79** · 09-25-2008, 02:29 PM

There has to be something else wrong? How do you know its the pump that is dieing? Have you replaced/tested the relay? What is the issue you are having?

**1998 T/A** · 09-25-2008, 03:14 PM

it was losing power so i though CATS, muffler guy tested for fuel pressure and he says fuel pump, it was throwing codes sayin o2 sensors were low voltage and running lean. the running lean and low fuel pressure is why he said fuel pump. make sense considering plugs/wires and injectors were replaced in may.

**Orcus79** · 09-25-2008, 03:22 PM

you can definatively if you are running lead by pulling a couple of plugs and having a look. I highly doubt that you would get 3 bad fuel pumps from GM in a row. Were the codes for both sides or one bank?

Cats can cause all sorts of strange issues. And believe it or not so can your MAF. Pull that out and give it a cleaning. It may not be measuring air flow properly.

**jigger1166** · 09-25-2008, 03:47 PM

You have other issues, it's not the fuel pump.
What DTCs are you getting?

**Goldcuffs** · 09-25-2008, 04:07 PM

Don't forget power and ground to the pump. Resisted grounds can cause problems.

**1998 T/A** · 09-25-2008, 04:11 PM

DTC's? pump was installed correctly it was put in by a certified GM mechanic. MAF is brand new and the CATS are fine.

**Goldcuffs** · 09-25-2008, 04:18 PM

Originally Posted by jigger1166

You have other issues, it's not the fuel pump.
What DTCs are you getting?

----------Codes-----------

**1998 T/A** · 09-25-2008, 04:20 PM

lean fuel, and o2 sensors both sides...o2 sensors were put in brand new less than 2 months ago

**Goldcuffs** · 09-25-2008, 04:27 PM

Do you know if they are checking fuel pressure or just condemning the pump due to the lean codes.

**1998 T/A** · 09-25-2008, 04:34 PM

checked fuel pressure he said it was pretty low...it explains the lack of power the first pump didnt really fail it didn't register the amount of fuel to the gauge. second one was good for a few weeks but when i got on the throttle it started fuckin up. this will be #3

**Goldcuffs** · 09-25-2008, 04:46 PM

Well like I said above make sure you don't have a resisted ground. Also you can try reading pressure at the fuel filter to make sure it's not something in the rail.

**Goldcuffs** · 09-25-2008, 04:50 PM

One other thing would be to make sure there is not a restriction in the return line.

**1998 T/A** · 09-25-2008, 04:50 PM

ya i guess we'll find out tomorrow when i pick it up i'll let you all know

**Goldcuffs** · 09-25-2008, 04:51 PM

Hopefully they don't just shot gun another pump in it just to get you out the door.

**astyles** · 09-25-2008, 04:54 PM

Originally Posted by Goldcuffs

One other thing would be to make sure there is not a restriction in the return line.

not to thread jack ,but im having simular issues........how would you go about clearing the return line?

**Goldcuffs** · 09-25-2008, 05:04 PM

Take the return of of the pump. I believe it taps in at the fuel filter or right near it. Then blow air through the line. Or you could skip taking it off the pump and blow through the the pump but I don't like to do that. If you do make sure you have the fuel cap OFF!

**1998 T/A** · 09-25-2008, 05:29 PM

hes good we've known him for over 10 years we take all our cars there he has a really good reputation in our town. so i dont think hed just throw one in and give me my car back

**Goldcuffs** · 09-25-2008, 05:40 PM

That's good. Let us know what you find out. Now I'm curious.

**1998 T/A** · 09-26-2008, 10:47 AM

Just got it back and it runs perfect...i talked to my mechanic and his son Bob works at a GM dealer here in sandusky. bob put the pump in so i know it was done right. not only that but last week he put a pump in a Silverado and trhe next day it was bad, he said GM is having trouble with their pumps lately so hopefully that helps anyone out there with the same problem.