RRAM

I just put a new fuel pump in 3 week ago. Jeep is not running well now, I can get it to idle and sort of rev up if I really feather the throttle. I put a gauge on it and have only 10psi. I put the same gauge on my dakota and it has 50psi.

I then went under and tried to see how the power was. I cannot get it turn on my test light. Not sure if this is normal. I thought I read where it should have 12 volts back there. I just unplugged the connection and tried my test light. I will go back under with a meter and see if there is limited power but I can most often get a glow out of my bulb even if power is low.

I can get a new pump under warranty but sure would like to make sure its the issue.

ET JEEP

The fuel pump should get 12v power when the fuel pump relay activates. The relay is controlled by the PCM. You can test the pump by putting a gage on the rail and running a fused power lead from battery positive to the fuel pump power connector. The pump should run and give you fuel pressure. If not, the fuel pump may have a problem.

4Doors

5 months after replacing my fuel pump assembly with a new Bosch unit, my WJ went from running great to barely running in 2 weeks time. Barely had 20psi. Looked like the pump crapped out so I had a new one shipped in on warranty, but on a whim I decided to also replace my fuel filter which is also a fuel pressure regulator, even though it was only 5 months old too. PSI jumped to over 50 and it has been running like a dream ever since. Might be worth $30 and 10 minutes of your time, it sure was for me. There really isn't a test for the filter/regulator so I just had to take a stab at it.

RRAM

Filter is brand new. I just am not sure what all the wires are for in that connection, or which is power and grnd. I am betting the orange heaviest should be power but I have no sign of power at the plug when unplugged. I have not tried it by poking the test light into the wire while plugged in. I need to know the which is grnd for a proper test I think.

ET JEEP

Looking at a schematic 93-94 Cherokee 5.2L it shows 2 wire connections. Orange (power) and black (ground).

On my 97 the fuel pump module has 4 wires. Two for the motor and 2 for the low fuel sensor.

How many wires do you have at the fuel pump? And what colors?

Just saw you also have an 04 GC. Which one are you working on?

RRAM

Mine is orange and black. I been doing more testing and downloaded a bunch of schematics off all data. I tested and my relay and swapped it for giggles. No change the pump does come on for a few seconds when the key is on. But only briefly. Which I am not sure is correct as I have it out of the tank not hooked to fuel lines.

With the key on I only have .03 volts on that orange wire. But it may be controlled by the pcm. I originally thought that the pump was always on and just recirculated fuel back to tank. Seems like maybe a bit more technical then that. I am going to return my pump under warranty. I feel bad doing that if not the issue but with it only hitting 9psi I could be wasting time chasing my tail.

I am working on the 93 beast. Gopher season I need to be out there

RRAM

Well fuel pump changed and running great. Now if only I knew what was killing my pump. Hopefully I was just a lucky guy and had 2 pumps that didn't last. If this one goes I think it will be redneck fix with an external pump.

juvius

just out of curiosity, what brand pump did you buy. if it's airtex, that would be the problem... they are horrible. i bought a new one off ebay knowing that for $79.00 shipped. I figured it had a one year warranty and was crossing my fingers it would work at least until i could afford a good one. got it in the mail and it was dead on arrival. i just sent it back and pulled a used one out of the junk yard.

RRAM

Not sure what name. The one I bought 3 weeks ago was supposed to be a better brand it was 100 dollars more then the first one I got. I'm crossing fingers toes and knocking on every piece of wood I see. .