Sir Jeep-a-Lot

Hey there everyone, I'm new to Jeeps, new to this forum, and new to working on vehicles in general. Firstly, this forum and a few others have been a HUGE help so far, so THANK YOU. Decided it is time to reach out and post up since my 93 XJ has been stranded down the road last 3 days.

The problem: replaced the entire fuel pump assembly(Airtex) about a week ago, drove fine for a few days...right before it stalled, I noticed a few misfires/hicups when I revved a little at idle right after starting. 5 minutes later there was 1 more hiccup and it just stalled while driving. No check engine light. I can hear the starter spinning and battery gauge says about 11-12v, but I don't hear the fuel pump turn on. Tried to jumpstart..nothing. Switched the fuel pump relay w/another one...nothing. Bypassed the ballast resistor...nothing. Everything seems to be working ok except the fuel pump isn't turning on. Any ideas why it wouldn't be turning on? I have a suspicion it may be something electrical since I don't know how a fuel pump could be installed wrong...is there something I'm missing here?

Tried to check engine codes, but can't get it to display for some reason...turned key off>on 3 times but the parking brake light, upshift arrow and check engine light just stay on.

Some background: this Jeep has been having stalling issues since I got it a few months ago. Its a 93 I6 4.0 HO w/ax15. Found the CPS was melted from touching exhaust manifold; replaced. Did complete tune-up: cap, rotor, plugs, wires, air filter, oil & filter. Cleaned throttle body. Replaced fuel pump & fuel filter. Added Lucas fuel injector cleaner.

Any help much appreciated, need to find some leads so I can get this thing off the road!

DFlintstone

...one easy check...there is a ceramic ballast resistor on the inner fender near the air cleaner. System voltage goes in the front, and a little less goes out the back, straight to the pump. You might check voltage there, check the connections on it. It's not necessary. If you don't mine a little more noise from the pump you can just bypass it...so there's one thing.

EDIT! Oops, 93?....it MIGHT, still have the ballast resistor...I think so....

car5car

Remove fuel pump relay and check fuel pump resistance by multi tester. Fuel pumps have 1.5-8 Omhs.

Flowpro

Have you checked for fuel pressure?

Airtex fuel pumps don't have a very good reputation around here for durability and quality. Carter or Bosch are what the majority of folks here will tell you to buy.

Here's what came out of mine this year.



I can't say for sure how long the Airtex lasted, only that I put in a new Carter assembly I bought online for about the same price as the Airtex one from the parts store.............. and couldn't be happier with it.

Sir Jeep-a-Lot

Yup, it did have a ballast resistor. That's what I thought may be the problem at first since the fuel pump & filter are new and switching the fuel pump relay didn't make a difference. Couldn't find a new ballast resistor locally, so I bypassed it but still no start. There aren't many more components to the fuel system, unless I'm overlooking something. Gonna get out there with a test meter and check the wiring going to the fuel pump for current.

One thing...the fuel pump was slightly crooked when I installed the new one, due to using the old O-ring bc I was having a hard time getting the lock ring on with the new o-ring. So it fit in there a little wierd once I tightened down the lock ring, but I'm pretty sure the rubber stopper is sitting in the hole and all. Could this have something to do with it?

freegdr

when you turn key on do you hear pump prime ?

freegdr

still got old pump?

Sir Jeep-a-Lot

Ok thanks, gonna get a tester and check everything.

And I haven't checked fuel pressure because 1)don't have a gauge 2) I just figured fuel pressure wouldn't make a difference if the fuel pump isn't even operating to create fuel pressure, but am I wrong?

I realized after buying it and reading around that Airtex pumps aren't the best, but could it really crap out after driving a few times? Seemed to be working perfectly at first. I guess the multi meter will tell all...

freegdr

still got old pump hook it to harness under xj turn key on see if it run my air tech worked 5 minutes it does happen plenty

Sir Jeep-a-Lot

Nope. And don't have old pump anymore...couldve put that back in to see if the new pump is the problem eh?

DFlintstone

I don't think being crooked would keep it from running, don't like that though. I forget if mine has a locator slot or something.

Yea, a cheap digital could make your life easier. Even the $5 Harbor Freight ones work OK, for a while...Of course any little 12V bulb could be rigged up as well.

It DOES seem people get bad Airtex pumps, (X2^), but verifying power and ground....that's just basic.

freegdr

cheap test light check harness takes 5 minutes or just take pump back say it quit simple as that

Sir Jeep-a-Lot

Ok thanks for the tips. Actually found the old pump at the bottom of the trash can lol, so ill hook that up first to see if new pump is the problem. If not, will check electrical current next.

2 people with bad airtex pumps? Now I actually wouldn't be too surprised...geez.

Sir Jeep-a-Lot

So I just hooked up the old pump to the harness, but it didn't turn on when I turned key to ON. Then I used a test light to check the wire harness for the fuel pump and nothing. Checked all the relays in the relay box and the light didn't come on for any of them...I used the negative battery post for a good ground, and the test light is working bc I tested it on the battery first. Where do I go from here?

freegdr

did you replace the first pump for maintenance or no fuel pressure ?