Fuel Pump Issue
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Somebody straighten me out here if I'm wrong. The pump basically works against a pressure relief valve to pump fuel in a loop. The pump side of the loop may be say 29Lbs, held there by the spring in the relief valve. Then the fuel flows freely back to the tank. On that pressure side some goes through the injectors to your engine.
If the filter is clogging, the pump has to work it's *** off to get the fuel through the filter. Might maybe make more noise like that, and cause the rig to run funky.
If you put a tire pressure gauge on the Shrader valve on your fuel manifold, you might get one reading before the gas eats the inside of the gauge. Might be better to find access to the right gauge. I don't know the pressure.
If the filter is clogging, the pump has to work it's *** off to get the fuel through the filter. Might maybe make more noise like that, and cause the rig to run funky.
If you put a tire pressure gauge on the Shrader valve on your fuel manifold, you might get one reading before the gas eats the inside of the gauge. Might be better to find access to the right gauge. I don't know the pressure.
Thread Starter
CF Veteran
Joined: Jun 2011
Posts: 2,448
Likes: 0
From: Colorado
Year: 1992
Model: Cherokee
Engine: 4.0
I'll definitely check out Rock Auto. Is that the kind of pump I need to look for though?
CF Veteran
Joined: Jun 2011
Posts: 2,858
Likes: 1
From: Nor-Cal
Year: 1990
Model: Cherokee
Engine: The venerable 4.0
True true...... yes. Rock auto stocks different brands of the correct pump. Enter year make and model and your options will appear. All stock specs. I hot a tps there for 30$ shipped. Works beautifully
Last edited by Slick761; Aug 22, 2011 at 02:06 AM.
CF Veteran
Joined: Jun 2011
Posts: 2,858
Likes: 1
From: Nor-Cal
Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Santa Rosa mah man. Indian village near coddingtown... my jeep is in petaluma right now while I'm going through it..... doing LOTS of work to it.
Thread Starter
CF Veteran
Joined: Jun 2011
Posts: 2,448
Likes: 0
From: Colorado
Year: 1992
Model: Cherokee
Engine: 4.0
So I'm going to try and replace the filter some time this week. I'm still getting a hissing noise when I start up in the back. When I remove the gas cap it sounds like pressure was built up. I'm just trying to figure out if I'll be fine driving this until I figure it out.
CF Veteran
Joined: Jun 2011
Posts: 2,858
Likes: 1
From: Nor-Cal
Year: 1990
Model: Cherokee
Engine: The venerable 4.0
You will be fine till it goes out. Mine started to die intermittently like it would die and eventually start back up. Then it finally crapped out completely.
Thread Starter
CF Veteran
Joined: Jun 2011
Posts: 2,448
Likes: 0
From: Colorado
Year: 1992
Model: Cherokee
Engine: 4.0
Alright guys, so I was on my way to class last night, and my Jeep wouldn't start. It was trying to start but just wouldn't. I replaced the fuel filter and the relay, and turned it on, started right up. Then it started to have the same issue as before, trying to start but not. Now in order for it to start and run, I have to pump my accelerator before and sometimes during when I turn the key.
Sign of needing a new pump?
Sign of needing a new pump?
Last edited by 92XJGuy; Aug 23, 2011 at 03:59 PM.


