Hi everybody,

A few days ago my XJ began stalling mid-drive, and then usually wouldn’t start again for a while afterward. I rented a fuel pressure gauge and tested it the next time it stalled and refused to start. No pressure, even though I could hear the pump priming.

I ordered a new pump (Bosch #67658), dropped the tank and cleaned it thoroughly, let it dry for two days and carefully put it all back together. No pressure. I checked at the fuel rail and got a dribble, then checked at the fuel line off the pump. Same dribble. I can hear the pump working, and the fuel gauge is reading gas at the first white notch.

I haven’t raised the tank all the way yet, and I only put in around 2.5 gallons in case I need to drop the tank again. Is there a chance it’s not reaching the gas?

I’ve also read in one of the forums about Bosch fuel pumps running backwards because the wires were reversed. Has anybody else experienced that or know how to diagnose it?

What are the odds that I got a bad fuel pump? Is there anything else I can try before I drop the tank again? I’ve sprayed starting fluid into the intake and it started long enough to burn it off, but then stalled, so I know the ignition system is working.

I’ve swapped relays around and excluded those as a possibility. Could it be the throttle pos sensor?

Some additional information: two years ago I had the same type of stalling issues, and a local mechanic told me I had a cracked head. I parked the XJ for two years and moved on, then my GF convinced me to get a second opinion.

Turns out the head was fine. I took it home, replaced the entire cooling system, pwr steering, coil pack bar, plugs, crank position sensor (what I figured the stalling was originally from), and cam position sensor. It ran great for a few weeks. We drove it 400 miles to the coast and back without a single issue.

Then, after thinking I had my Jeep back, it began stalling. Stalled at 70mph on the freeway and wouldn’t start again for 10 minutes. Tested the fuel pump, got no pressure, and replaced it.

I’m now officially stuck.

Any advice or suggestions, or even elimination of a few of the possibilities would be GREATLY appreciated. I’ve had this Jeep since I was 18 (now 32), and I’m now atoning for not taking better care of it!

Thank you
John

 

Did you install a new fuel filter?

 

It's a 2001, so the fuel filter is part of the fuel pump module. Sorry, I should have been more specific. I replaced the entire module, which contains the pump, filter, and pressure regulator.

 

If it were me..........

I'd remove the hose/line from the filter/regulator and use a piece of fuel hose that I would drop down into a jar/gas can and have someone turn on the ignition to see if the pump is actually pumping. If it is.....there must be some kind of clog in the fuel line from the tank to the manifold.

 

I removed it at the point where the feeder hose that comes off of the pump (around a foot long) connects with the main fuel line and had someone turn on the ignition. It only dribbled. I'll remove that feeder and check it for clogs.

Any idea how much gas I should see coming out during the priming stage? It should come out pretty forcefully too, right?

 

Yeah, a bunch.

You may have a bad regulator.

Have it replaced/warrantied.

 

I pulled the pump back out and looked it over. It doesn't have the same Chrysler markings or labels as the ones I've seen online, and the spring-loaded mechanism isn't springy. I'm guessing I got a fake or a defective unit.

Going to return it and probably spend the extra for a Mopar unit. Thanks for your help, I'll let you know what happens.

 

Well, I ordered a replacement fuel pump, installed it, and it worked great. Engine fired right up, drove it for 2 or 3 miles, got it up to temperature, then went home. Started it a couple more times after that (while the engine was still hot) and it fired right up.

I went inside for about an hour, then came out and tried to start it again (temp in the 100-120 range) and it wouldn't start. Checked pressure at the fuel rail and all was good there. Sprayed starter fluid into the intake and this time it didn't seem to fire up like before, suggesting there's now an ignition problem? What the hell, it's all new and was just working fine! I also tried swapping relays in case it was the ASD, but nothing changed.

I went ahead and replaced the TPS on a long shot. No change. Went out the next morning when the engine was completely cool and it fired right up like it was brand new. The IAC was replaced a few years ago, so what else is there but O2 sensors and the PCM that might be affected by heat? The check engine light always comes on for around three seconds, even when it won't start.

Any ideas?