Cherokee_of_Tennessee

So, after leaving the jeep at the dealer for a week before Christmas, it appears the root cause was the fuel pump. The dealer diagnosed this in one day. The technician/mechanic said he was doing a distributor test and caught the fuel pump dropping out intermittently. I bought a delphi fuel pump from napa and gave it to the dealer to install, because I just don't believe a mopar fuel pump is worth twice the money. I used to work for an automotive company that makes fuel pumps. The dealer called me back the next day and said the delphi fuel pump was dead on arrival. Went and got the delphi pump from them, took it back to napa, bought a "precision" fuel pump from O'reilly's and had the dealer install it. I have been driving on it for over a week and I have had no issues. Jeep purrs like a kitten and I am getting 18 miles to the gallon. Which isn't surprising considering I have changed damn near everthing that could cause bad gas mileage during this whole ordeal.

Point of note: I replaced the fuel pump 3 years ago with a "Airtek" fuel pump from Autozone. This pump only had a 1 year warranty, so I was stuck with buying a new one. Autozone told me they still sell the Airtek with a lifetime warranty. When I asked what the difference was, they said no difference, just increased the warranty. No thanks, no matter what kind of warranty it has, I would rather not get stranded on the side of the road in 3 years.

Hopefully this issue is closed and someone on here will benefit from my experience. I will repost in a few weeks just to make sure all is still well and we have nailed the root cause.

TwoXJS

Never get an Autozone fuel pump....Made that mistake on a Ford F-150 we had. Pump went out, bought an Airtek because it was the cheapest. Ran good for about....oh, three days, then went out. Autozone refused to warranty it and said "Installing it voids the warranty". O.o

Cherokee_of_Tennessee

Yep, I agree. In fact, I am starting to question everything I buy at Autozone. I have bought several components that were dead on arrival right out of the box, or it was the completely wrong part out of the box. I had two universal joints that were wrong, and I didn't realize it until I already had the old ones out of the drive shaft. Luckily I was at the DIY Auto Skills Center on post and one of the on duty mechanics ran me over to Autozone to lay knuckles on thier head and get the right ones. O'Reilly's seems to give me the best success. I don't get as good a military discount at O'Reilly's, but its not worth the headache to take a chance on Autozone anymore.

By the way, Jeep is still running great. Keeping my fingers crossed.

Cherokee_of_Tennessee

I have been talking with slowjunk in pm's and he brought up something I think should be mentioned here. When I had the old fuel pump (airtek from autozone), I would here a clump-clump.......clump-clump..... clump-clump.... coming from the fuel tank after stopping and shutting off the engine. I assumed it was the gas just sloshing back and forth in the tank. I could also hear it with the engine running while stopped at a redlight. I didn't think it was significant until slowjunk told me he was hearing his do this, and he has the same symptoms I had. Also, I don't hear it at all with the new fuel pump. So, I have to think that the fuel pump structure was weak since it was made of plastic, and it must have actully been flexing and moving inside the tank as the gas sloshes it around when you hit a bump or make turns. I used to work for an automotive company that makes fuel pumps. The gas sloshes around in your tank with some pretty agressive force and can actually break a weak-designed fuel pump. The new fuel pump ("precision" from O'rielly's) is made out of all metal. So, the moral of the story is, if you hear that clump-clump.....clump-clump.. in your tank, you might want to make sure your fuel pump is well secured in the tank, and does not have any breaks in the structure holding it in the tank.

By the way, still holding strong with the new fuel pump. No issues and the orignial symptoms have not returned yet.