Cherokee_of_Tennessee

Wanted to bump this thread. I think there should be a sticky about fuel pump failure symptoms. Not all are the same, I understand, but this symptom has happened to me and I wasted $1500 between Midas failing to diagnose the problem correctly, and then biting the bullet and having the dealer diagnose and replace the fuel pump. I now have a 1999 and just started doing this tonight. Here are the symptoms I experienced tonight, and two years ago:
1. Severe bucking on acceleration, just like jenz said about it feeling like its a straight drive and you don't know how to let off the clutch.
2. Let off the gas and it seems to pick back up, but very weak throttle.
3. Often times it completely dies, and I sit on the side of the road for about 20 min, start it back up, drive for maybe 15 or 20 min, dies, rinse and repeat.
4. Will not immediately re-start after it dies on the road.
5. Feels like the more pedal you give it, the worse it dies. Makes sense cause when you open the throttle and give it more air with no gas, it leans it out to thin and dies.

So tonight my 1999 started acting up on the way home. Same exact symptoms. I just barely coasted it in to the drive way when it finally gave it up compeltely. Could not get it to restart. I was thinking maybe the gas gauge was stuck, and I was out of gas. I dumped a 5 gal can in that I keep for emergencies, and still not start. It would turn over, grumble a bit, then die. I waited 30 min. Went back out, started right up. I heard a very soft high pitched whine coming from the fuel tank. Sounded like the fly-back transformer in an old CRT television. If you have heard that ringing sound you know what I mean. Anyway, just as a hoot I decided to bang on the bottom of the tank with my fist. The jeep immediately died. I started it back up no problem. Still hearing the high pitch whine that I suppose is a bearing in the fuel pump that has given up its spirit. So I am going to go get a fuel pump tomorrow or the next day when I get time ( i am a full time Soldier with little disposable freetime) and will post back my results. I'm betting I am right in my diagnosis. Anybody want to bet against me?

EDIT: By the way, I wanted to tell you all that when the dealer and Midas both checked the fuel pressure, it was just fine. The only way they caught it was when the dealer was getting ready to do a distributor test, he noticed the fuel pump voltage acting flaky. This was an Autozone spectra fuel pump that was 1 year old. So, I bought a Delphi fuel pump from NAPA and gave it to the dealer to install cause I was not going to pay dealer prices. It was dead on arrival. Got another one from Autozone. Again, dead on arrival. Finally got a Precision fuel pump from Orielly's, and it has been going strong for 2 years now. Don't think just cause you replaced the fuel pump recently that your problem cant be a fuel pump. I wasted $1500 on this flawed assumption.

CCKen

Most of those fuel pump modules you mentioned are crap. The best fuel pump module is Bosch, with Carter coming in second (and a bit cheaper). Bosch was the original factory installation.


I installed a Carter several years ago and it is still running strong.

Cherokee_of_Tennessee

Yep, it was the fuel pump. Put in a Precision brand fuel pump a few days ago and it is running like a champ.

CCKen

I may be wrong, but I think Precision is a rebranded Airtex pump.

Kenny Groff

did you figure this out? My 94 is doing exactly the same thing

Alex Pena

I had this same issue. Replaced O2 sensor that wasnt it. Replaced TPS and that fixed my rpms jumping back and forth while driving around 35-40 ish mph.

Shane Staton

I have a 01 Jeep Cherokee it drives find at first then after awhile it will random start misfiring bogging out when you driving popping back threw the intake and even cut off. It will start back sometimes but its running so rough it cuts off . If you let it set for awhile it'll start up and fine. I've put a new coil and plugs in it . It seams to have good fuel pressure at the fuel rail. Any ideas would be appreciated

BillyBoy

Had hesitation on acceleration. Had random no starts requiring 2 turns of the key. Finally had stalls driving. Oriely rents fuel pressure gauges. Test it. A few times. Warm and cold. Mine was in the 20s and sometimes the 30s.

They SAY the pumps either run or quit. Maybe they are correct. In my case, when I dropped the tank, BEFORE installing the new pump... I looked INSIDE the tank with a flashlight... don't use a lighter. There was a build up of tar or putty in the bottom of my tank. Had to literally scrape the stuff out and clean it and flush it multiple times before installing the new.one. Ran seafoam thru on the first few tanks post put together...good as when she was new. 200000 miles of sludge and tar buildup was messing with ol girl.

Good luck. Have fun. GOD Bless.

Cherokee_of_Tennessee

I have had hesitation issues plaguing me since I have owned a jeep cherokee. They just kind of dont run good when they get old, until you find that one freaking sensor or loose wire or bad ground that caused the problem.

Recently I had a hesitation problem when turning left or right, or driving on steep incline in reverse. Drove me absolutely insane. Could not figure it out. Finally I was doing something else in the jeep and noticed the battery wires were loose as a goose at the battery terminals. I replaced the sorry lead terminal connectors with some zinc plated steel ones and cranked them down good and tight. The problem went away for a while. When it came back, I noticed the cables where I had bolted them to the terminal connectors were coming loose. So how in the heck are the cables continuing to work loose??? THE BATTERY TRAY IS BROKEN. This lets the battery bounce around in the mount too much and works the cables loose. I ordered a new metal battery tray from amazon for about $65 and will be installing it this weekend.

Loose cables and wires are a huge pain in the *** to diagnose and catch. But when you start having un-explainable intermittent issues, a loose wire or cable is usually the gremlin. If all else checks good, wiggle your cables and wires associated with fuel and ignition. You just might catch your gremlin.

jon71203

looked around the forum and i think this thread is as close as it gets. my 97xj with 293k has just started to occasionally stall on acceleration or coming to a stop. it feels like a fuel issue. i can get into 3-4k rpm and it'll power through the hesitations but obvious that doesn't work for around town driving. like i said, its also intermittent. today when it was stalling on acceleration i took this video to show what was happening with the rpms and lurching. i also noticed that when i really pushed the pedal down to give it gas and keep it running, that crap (the black stuff in the picture) was coming out of the exhaust. took a picture of that as well. any thoughts? i know my cat and 02 are shot for what thats worth.

trying to figure out the video...sorry....more to come

shiloh faulk

Good evening y'all, I'm new to this forum stuff so not sure how it works,

But I have a 1991 Comanche 4.0L automatic, it'll drive great no problem, but once I've driven it around town for a bit and it warms up it'll buck and sputter going into 2-3 gear,

dogderr

Besides fuel pump,if you put foot to floor, revs high, but no power, long to shift and oil pressure goes threw roof,yet oil level is full try this disconnect exhaust befor cat test run it will be loud. but if power comes back ,shifts normal:you got plugged cat or plugged muffler .air back pressure threw valves causes shift problems like auto trans is shot.I've had a 93 Grand Cherokee Base yj 4.0 that bought in 06 forr 300. gone threw every problem,fuel pumps in tanks must be in gas to keep cool 1/2 tank or more if you ride 1/4 or less alot you will burn it up,it will heat up and ;stall ,jerk,gallop spit sputter like timing is off,you'll have to feather gas peddle to keep running after heats up also will smoke like hell to even backfire to..may run great in winter,suck in summer,pumps are tricky,ive seen wiring go bad so i ran a neg ground from battery to tank never worry on that one run a hot but to battery leave unhooked at battery until problems start then run hot see if it fixes,when hot is not in use make sure doesnt touch frame or you'll short out your pump.

RocketMouse

Just looks to me visually like a bunch of carbon that was built up in the exhaust pipe that was "reconstituted" when you had more water vapor coming out. Probably mix between atmospheric conditions and vehicle condition(temp, etc.) were just right for it to mix and freak you out. Do you notice any smoking either at idle or acceleration? If not, I wouldn't be too overly concerned about it. if it's a "one time" kinda deal. If it continued, I'd start checking other things as a sign of internal wear.

maillady1960

I have a rhd jeep Cherokee, I have noticed many times that it runs fine until I cut it off to go in a store or in the post office at the end of the day and when I start up its fine but when I accelerate it cuts back as if will stall. I usually pump the accelerator on it will pick up and I drive on with no problem. My husband said he was not sure why this seems to help since it has no carburetor. it has recently had coil and all electrical associated with coil replaced so I don't think any of these are the problem. fuel pressure is fine. Any ideas? Not a big problem just wondered if anyone could diagnose. It is a 1998 and has been doing this since about 2000.

Hellz

So it seems like in short i'ts the fuel pump.