Edmunds Answers


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  • avatar markjeffrey 11/28/08 9:25 pm PST

    The dealers service dept. is able to connect a computer to the electronics imput. This will be a you drive it around for a time, days or weeks until it acts up again. when it stalls this time the computer will record what caused the problem. This will ensure the right thing is fixed. mark


  • chaingang2 10/03/08 9:42 pm PST

    do you use regular fuel mid- grade fuel or super

  • zaken1 10/03/08 9:57 pm PST

    I would suspect that the distributor ignition pickup is defective.

    I hope this helps!!!

  • canddmeyer 10/04/08 7:12 pm PST

    A defective ignition switch will also cause the same symptoms.

  • rebejeep 10/06/08 11:43 pm PST

    I use regular unleaded gas. The ignition pickup has been changed. It's still at the Chrysler Dealer. I'll find out more tomorrow. If they solve this problem I will certainly post the results. Thanks everyone.

  • on_point19 10/16/08 11:36 am PST

    i had the same problem and replaced the same parts on my 97 Jeep Grand Cherokee 6 cylinder. I had a code for the ignition coil, which was replaced. Dealership found that it was the ignition coil driver on the control module for the engine computer board. Hope this helps.

  • rebejeep 10/16/08 4:35 pm PST

    I picked up my car Tuesday 10/14, and yesterday it STALLED again. I'm going to bring it back to the dealer. I was charged $730.00 and the problem continues. They need to give me back my money. They changed the MAP sensor, Crank sensor (2nd x. The first mechanic already changed the Crank Sensor). They did a fuel injector flush and a throttle body cleaning. We already changed the inginition coil, cap and rotor, oil change.

  • latisha12 10/24/08 4:38 pm PST

    My 1997 Jeep is doing the exact same thing and has been with a mechanic for the past 2 weeks. Same parts (plus more) have been replaced, including 5 crankshaft positioning sensors. Each time they think the problem is fixed and then it starts doing it again. If you find the solution, please post it. Thanks!

  • karjunkie 10/24/08 5:26 pm PST

    I have read several threads on this problem. One engineer discovered that the the outboard PCM cover screw was shorting out the circuit board. Hva e the dealer check this, it could be your problem. Good luck!

  • latisha12 11/05/08 3:12 pm PST

    I have had the screws in the PCM shortened (put 3 washers between the screws and cover) and it appeared to have fixed the problem, for a week or so anyway. I believe the backfiring has shot the catalytic converter and that now has to be replaced. However, last night driving home (doing about 35-40 mph) the car just stopped acclerating. I was pushing the gas but nothing was happening. Then all of a sudden it started accelerating again. Could the catalytic converter cause this or is it more likely that the PCM is having problems again??

  • karjunkie 11/05/08 3:25 pm PST

    Latisha12: that sounds more like your throttle position sensor malfunctioned momentarily. That can happen in cold weather. You can have the mechanic test it with a voltmeter. It is a quick test. Good luck!

  • d07 11/22/08 12:09 am PST

    Here's a link to a similar question that I've tried to answer within the Edmunds forum. Hope it helps.

  • markjeffrey 11/28/08 9:25 pm PST

    The dealers service dept. is able to connect a computer to the electronics imput. This will be a you drive it around for a time, days or weeks until it acts up again. when it stalls this time the computer will record what caused the problem. This will ensure the right thing is fixed. mark

  • etarape 11/30/08 2:11 am PST

    Thanks everyone for your input. The mechanic at the dealers did hook up the computer and when it stalled the code came up ignition coil. That was changed and it continued to stall.

    After being in the shop for almost two weeks I finally have my car back. The last thing they changed was the PCM (computer box). .

    After almost $3,000 in repair cost since January of this year, 2008, I hope that it’s finally fixed. I drove it to
    Livermore, CA today which is 60 miles away from my home. It didn’t hesitate or stall. I’m keeping my fingers crossed. The car has been driven only 3 days since I picked it up last Wednesday, 11/26.

    I'll update this posting if it stalls again.

  • chefsm1 04/26/10 10:47 pm PST

    Same problem with my 97 just changed the ignition switch problem solved

  • sickmade23 09/25/10 1:47 am PST

    1997 Jeep Grand Cherokee Laredo stalling problem. 6 cylinder 4wd 111,000 miles. No codes.

    i have had the same issue it will die about 10 times a day some times it will start right back up and other times it takes a while and has a bad smell when it stalls out ive been to six techs and no one knows but one did tell me the the pcm was going bad well i replaced it and it worked for about 2 months, long story short ive replaced pcm 5 times now i buy a refurb pcm every 2 to 3 months just to keep my wheels turning anybody please help us.

  • sickmade23 09/25/10 5:35 am PST

    went to dyingjeep.com and bought the repair mod to fix this problem with my jeep i will be doing the repair tomorrow and will inform you of the results if successful i will post the information of the repair and how it was done just because i dont think 20 dollars for the info is fair to the people who spent so much already trying to fix the problem like myself.
    give us a break on this problem jeeeeeeeezzzzzzzzzzz.

  • crazymacaw 10/09/10 2:04 am PST

    Curious if that dyingjeep.com mod worked for you. I don't mind paying them $20 if it actually works. I'm curious though, without letting the cat out of the bag as it were, does the mod require you to open the PCM or is it all done externally.

  • sickmade23 10/20/10 12:19 am PST

    FINALLY.............. YES ITS FIXED..

    here how you fix this problem.
    disconnect battery and remove pcm.
    on the face of the pcm is two small torque skrews (not the pcm mounting skrews) but you will see them. remove a skrew one at a time and put (three) 4mm flat washers on the skrew and skrew back in, each of the two skrews should now have three 4mm flat washers added. now with both skrews replaced with three 4mm washers re-mount pcm, plug in each harness and re-connect battery.

    sounds stoopid but it worked i guese the skrews are to long and grounding out the pcm dont know why jeep did not do a recall but hey there you go guys hope this helped. worked for me 10 cents is all it cost. after spending near a thousond trying to fix this issue.

  • crazymacaw 10/20/10 3:23 pm PST

    Hmmm, you paid $20 for someone to tell you to add spacers to mounting screws.
    That "mod" has been circulated for free for a couple years now. what I had done was to just replace those screws with shorter ones. Mine ran great for about 2 weeks or so then started acting up again. I actually opened my PCM and looked inside and what I found is that those two screws don't and can't hit anything inside. Inside the box there are two PC boards, one is mounted to the cover with those two screws and the other is in the case side. The two connect with a set of long pins when assembled. What I found in mine was a coupel of broken solder joints on the outer PC board.

  • jeeplady2 11/11/11 1:51 pm PST


    My Jeep began to stall, lose power, shake and backfire. Thought it happened just on low fuel or turning corners but began to happen more frequently. Had many parts changed, but still no solution and hard to diagnose without no engine light on.

    Solution for me was: PCM unit on firewall. With plastic overflow reservoir moved out of way of PCM, I gently moved (back and forth) the connector closest to engine on PCM, with jeep on. This would be the one for me that would get jeep to start stalling. We rigged a support piece for PCM to give support (support from behind, not pulling from front) and this worked so the unit did not wiggled or shift when engine was on. No more stalling or dying out. Again, this worked for me.

  • captzola 01/03/12 6:30 pm PST

    Thanks everybody. same stalling problem with my 97 JGC 6 cyl.

    sounds like either the screw problem or loose connectors to the pcm. before i found this forum, i change plugs, wires, distributor cap, rotor, coil, and these did not stop the stalling. will check the torx cover screws and shorten them to 1/4" instead of 1/2". will report back my findings, thanks again for all your help and posts.

  • connielee 08/15/12 5:24 pm PST

    Do you have any updates? My 1997 JGC is doing the same thing.

  • bleanza 08/22/12 10:13 am PST

    I was encouraged to see that someone posted a similar problem in August of 2012. I too am having a problem. We just bought the 1997 Grand Cherokee with no problems on the test drive, but a day later it stalled for the first time. Yesterday it kept stalling and started backfiring really bad. I am going to tell my husband about the screw spacing, but if that really is the problem, you would think Jeep would have posted it as a problem and issued a recall by now. I will let everyone know if that seems to be the problem after we've tried it and run it for a while. We had already did the tune-up and replaced the ignition coil and crank sensor before coming upon this site.

  • millicent1 09/10/12 3:38 pm PST

    Found that the outboard PCM cover screw was shorting out the circuit board. Chrysler PCM p/n P56028412, s/n TEH106636023.

    Short story long: I have a 96 Grand Cherokee 4.0L, 125,000 miles. Several weeks ago, I started to have stalling issues. Hot or cold, dry or wet, first drive of the day or last, it didnt matter. The engine would cut out. It felt like it lost all electricals.
    At the time it was showing an ASD relay code. Swapped the ASD and A/C relays. Same problem. I didnt have time to look at it, so I had the dealer go through it. After 2 days and $200, they called and said it was the ASD relay, and that they put in a new one, and its all good. Um, ok, maybe I missed something. Im a trusting soul, but lets see if this fixes it. The next day the problem was back. I went back to the dealer and they basically said, We dont know what it could be, good luck with that. Now my wife knows why I dont go to the dealer. By the way, the old relay tested good.
    My turn. Being the methodical aircraft mechanic that I am, I grabbed a multi-meter, contact cleaner, and wiring diagrams. I cleaned connectors, ohmed out wires and sensors, checked for power and grounds. Everything checked good. By now, its showing ASD, crank sensor, and primary ignition codes. Then, with my wife trying to start it, I wiggled the connectors on the PCM. Every time I wiggled the gray C3 connector just right it would run. When I let go, it would die. So I took the connectors apart and tightened up the crimps (I dont recommend doing this without the proper extractors and crimper). Threw it back together and BAM! Same problem. Well, time to bite the bullet and check for bad solder joints on the PCM board. I took the cover off of the PCM and realized that looking through the potting compound is like looking through Guinness Stout. But, I put it back in and hooked it up. It started stronger than ever, and didnt even think about stalling. Yes! I figured that I finally got the connectors sorted out, so I left it over night to cool down. Got up the next morning and it started right up and wouldnt stall even when wiggling the connectors. So I put the cover back on, put the PCM back in, hooked up the connectors, and BAM! It wouldnt start! That was the point when my wife asked, Hows it going? And I, being the methodical aircraft mechanic that I am, said, what the ----? Thats when my wife turned around and went back into the house. While smoking a pack of cigarettes, I thought, Gee, it runs with the cover off, but not with it on. DUH, wonder what it could be? So I backed out the two screws that hold the cover on and BAM! It started right up. Then, while it was running, I tightened the outboard screw and sure enough, it died. Yes! Aircraft mechanics love it when they can make things stop working. I installed new screws (1/4 long, factory screws are 1/2 long Torx head), and shes been running great ever since.
    Now, will this fix a bad crank sensor or idle air motor? No. But it is an easy trick to try before going to the dealer and having them throw expensive parts at your Jeep and seeing if any of them stick. Just back out the cover screws about 1/8-1/4 (dont worry, nothing will fall apart inside). If it fixes it, great! Spread the word. If not, use logical trouble-shooting steps. Learn the systems what will and what wont cause the problem. Good luck.
    As a side note, if you want to see a service managers eyes pop out of his head, tell him that you want your money back because your not going to pay them to trouble-shoot a design defect. Its a glorious sight

  • evoxj 10/02/12 8:40 pm PST


    I just wanted to thank you for your post. You just saved me a lot of money. This has been bugging me on my 1997 XJ. Some of the issues that I am having is when I turn my wheel I am getting a loud popping noise. So I found that it was the upper bracket that goes to my stablizer Z bar to the drivers side sub-frame/frame. I have a 6 inch lift with 33's on my jeep. So the popping is just some loose bolts. But when I move my wheel back and forth with the popping my idle goes up. When I pop it back into the straight posistion then the idle goes down or even dies out. So when I am driving at any speed it will jerk and almost stall out or not get any gas. But when my drivers wheel is straight then it drives fine. Well I am going to test out the PCM screws and take your advice tomorrow morning and will repost my results. Hoipefully I can tighten all of the bolts and get rid of the popping sound then I am going to get an alignment.

    List of parts replaced this year:

    Idle positioning sensor



    Fan shroud


    Wheel hub assembly

    Skyjacker 7000 shocks

    Magnaflow exhaust (no cat)


    Tune up was done last year.

    This jeep runs like a champ when it wants to. I just cant belive that the front end would make it run like crap. Must be something in the computer telling it to stall when the alignment is off???


  • mickael 02/22/13 12:20 pm PST

    pleases answer

  • kelso97 04/03/13 5:02 pm PST

    I own a 97 Grand Cherokee Laredo with a 4.0 engine. It has 128,000 miles and has experienced stalling or just plain quitting while at road speed. Two years ago, check engine light came on, stalled never to refire. Code for crank and/or cam sensor. Had replaced and it ran fine for one year. Check engine light on again. Code for ignition coil. Had replaced and ran fine for one year. Had washer spacers put under PCM cover screws.

    A few months ago whole scenario started again but NO check engine light. When first started it ran and idled fine but put under load it would just die. Most of time would restart, drive quarter mile come to stop and die, restart, drive 30 mph and would just quit (very dangerous), pump throttle and for some unexplained reason it would refire. Once warmed up drove for 10 miles and could not get it to stall. What the heck is going on?

    I was not going to chase hundreds or thousands of dollars to solve this, so… removed idle sensor and cleaned, cleaned throttle body bore & idle bore, checked vacuum lines. Removed MAP sensor checked and appeared OK, checked throttle sensor, zip tied connectors to PCM. Used LPS contact cleaner (great product) on all sensor connections. Took for test drive…and stalled.

    Got thinking, just cleaned and reconnected everything on positive side (+), what about negative (-) side? Cleaned battery terminals, cleaned chassis ground adjacent to battery on upper fender well, disconnected ground gable from block to battery, cleaned and reinstalled. Failed to mention, have a valve cover leak at rear and when checking ground stud on block (between #5 and #6 spark plug) it had dirty oil on it. Dismantled connections at stud and were oil soaked. This is the PCM ground. Cleaned and reinstalled.

    Driven car for 100 miles, stop and go, highway and hard braking and NOT A STALL. I could have shortened the blog and just said….CHECK THE GROUNDS!

  • 96jeepdave 08/14/13 1:34 am PST

    Oh, I have been through the ringer with this cutting out & sputtering when hot problem on my 96 Grand Cherokee. But, finally fixed it with a replacement PCM.
    It has been doing this for 4 months now. I would have to let it sit for 2 to 3 hours & when cool it ran good again. I even got through a 4 day trip to Moab, Utah where I had to sit on the trail once or twice a day till it cooled down enough. Finally, at home, I took the PCM out from the firewall behind the coolant bottle & cracked it open to see what might be wrong inside. Well, I broke a resistor on the edge of the board with my flat head screwdriver. Nothing else looked bad & all continuity tests were good so I soldered in a resistor & put it back in. Then, none of my gauges & the fuel pump would not come on. It cranked but got no spark & no start. I actually killed my PCM. I freaked at first. The dealer wanted $700 to replace it & program the new one. I called a friend who suggested a good junk yard that had 2 jeeps of my year that he saw the PCM's still in them. I made a mad dash down there & got both PCM's for less than $100. I noticed that on the jeep that was 6 months newer than mine the small number on the bottom right was 1 # later than mine & the jeep that was 6 months older than mine the # was 1 digit lower. Older jeep= zbyaa Mine= zbyab replacement=zbyac. All the other numbers were similar but but not the same. So I tried the older one first & all gauges & fuel pump came on & it started. I was extatic! But, it ran really rough . So I tried the newest one, zbyac, & it ran great!!! It now idles, shifts, accelerates better than ever & has more power. I didn't know how degraded it was till now. It hasn't cut out or died yet & I haven't even taken it in to get it re-flashed. Why shoud I ??? Maybe I'll have to for emissions but I'll see if it will pass without the reprogramming. I was ready to replace the fuel pump & crankshaft position sensor next but, now I won't have to.

  • sokon 01/03/15 9:02 pm PST

    Change the ECM engine Computer module. I changed everything like you. Finally I changed the engine Computer module. Its been runnning great ever since.

  • fishwanda1 02/18/15 5:25 pm PST

    I'm seriously about to go nuts. Is there not a simple answer after all this time? I've been throwing parts at this jeep for some time now. Finally took in for emissions recall. I prayed this was the answer but now it's worse and NOW i get catalytic converter error code where i wasnt before.

    can someone please help!

  • fishwanda1 02/18/15 5:34 pm PST

    I have more thsn two screws on pcm cover. Which screws are we talking about exactly. Any pictures? I can see s one screws and nowhere near firewall

  • fishwanda1 02/18/15 6:01 pm PST

    Go to youtube and type the following in a search. 1996 jeep cherokee pcm repair. Find vidro called, Jeep pcm fix look. This is my next big adventure and actually feeling good this will fix the problem once and for all! it's what you're basically getting when you buy a rebuilt pcm. If you're all thumbs and clumsy, I'd get a patient friend to do this. Be careful taking this apart!

  • johnb217 10/09/15 1:47 pm PST

    Mine was dying sparaticaly no codes showing got it started & to parts store .. wiggled pig tails going into CPU & it died ... went in got can of electrical cleaner & flooded pig tails & cpu ... seems to have solved it...

  • meetodude 07/15/16 6:48 am PST

    it's the computer I have had to change mine twice and the previous owner once.

    Only in a jeep yea don't get me startes *or plz start" first it starts hard starting takes a bit longer idles rough and then it will take a bit start and leave you with a false feeling of confidense then the further you get away from your home the more likely it will leave you afoot.

    I think the default code for everything on a jeep is the cam sensor I think it is the first or last in the list so BANG any code check from a hand held to a professional shop same thing cam sensor but if your replace it that has never solved the problem out of one year I have been able to drive mine 9 months all the codes I ended up replaceing the fuel pump talk about a costly pain and that wa not it so I replacce the distributor, cap and pickup coil NOPE still would not start or run consistantly untill I changed out the computer.

    People only know what they are born into I can say that the worst thig EVER was the computer integrated inot every system all we ever needed wa fuel injuection and electronivk ignition all the rest is lazy or ignorant people require a heat sensor in their heated seat because they cannot tell its not working because that is where their brains are.


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