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Thread: The stalling and restarting problem AGAIN! :-(

  1. #1

    Wink The stalling and restarting problem AGAIN! :-(

    Well I am now faced with the infamous Grand Cherokee sporadic stalling and restarting problem. Yet I am amazed by the years worth of stuff online about people with Jeeps having this exact same problem, yet there does not seem to be any surefire fix for this problem, where even the Jeep dealers can not fix this problem right away. Yet mainly I’m trying to get some answers to see what I can do myself while trying to keep from tossing tons of money senselessly at this problem. I would like to explore a few do-it-yourself options before taking it to my mechanic, because he may charge me a fortune to try to find the problem by trial-and-error . . . which worries me, since I read of so many people saying that the Jeep dealer could not readily find out this same old stalling and starting problem that seems to have plagued Jeep Grand Cherokees for many years.

    I have a 1996 Jeep Grand Cherokee Limited, with a 4.0 6 cylinder engine, with 2 wheel drive, and with about 165,000 miles.

    Upon reading about this problem in so many online forums, I was wondering what was the “one thing” that “you did” to your Jeep Grand Cherokee that fixed this problem? When I say fixed, I mean what was the “one thing” that you did that totally stopped your stalling and restarting problems for at least 6 or more months?

    To keep things easy and simple, it is not necessary to read beyond this paragraph, unless you want to know some of the background of my particular situation and problems. Mainly I am only looking for the “one thing” that "you did" that totally stopped your stalling and restarting problems for at least 6 or more months, so I can start experimenting with those solutions to see if I can quickly fix my stalling and restarting problems.

    Thank you.


    If you want to know more background on my problem, here it is:

    I have the classic case of my Jeep is unpredictable, in regards to the stalling and starting problems. The engine tends to bucks at least 3 or 4 times upon driving it for 5 to 6 days. The engine now dies within 15 to 25 minutes of driving it . . . sometimes it will start right back up or at times, it will take 1 to 5 minutes to restart it. Yet if I dare park it (after driving 15 to 25 minutes), it is a 50/50 chance that it will restart. If it doesn’t restart, it will take about 2 to 3 hours before it will start. Yet it amazes me that I can try starting the engine to the point of draining the battery down and the engine will not turn over, yet if I leave it sit for 2 to 3 hours, it quickly starts right up with no hesitation.

    Though the CEL has not been on in over 4 months, my mechanic said it only had one code, and the code was a PO138 Oxygen Sensor / Bank 1 Sensor, which he said would not be related to the stalling and starting problem. He said that he thinks the problem is electrical or it could be the fuel pump.

    I had heard that adjusting some screws by the PCM (behind the coolant reservoir) fixes this problem.

    I had heard that the CEL reader should pick up a code “11" (no crank shaft signal position signal detected), then once you replace the crank shaft sensor, this fixes this problem (I do not have this code reading).

    I have also heard that by replacing various sensors, this stopped this problem.

    I had heard that replacing the PCM fixes this problem. I wonder can I get a PCM from a salvage yard? I sure don’t want to buy a brand new PCM and it turns out that is not the problem, because I have heard of several people buying brand new PCM (for $200+) from the Jeep dealer only to discover that did not fix their stalling and starting problem.

    Yet all-in-all, it sounds like trying to fix this problem could be just about anything and that I just should be prepared to throw out lots of money trying all of these various options until the problem is fixed. Yet I'm just trying to avoid this, since I'm living on a very tight income and budget (due to our poor economy) and I can't afford to get another vehicle at this time.

  2. #2
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    On most 96-97 4.0's this is caused by the PCM connections inside of the PCM making a bad connection. This can be resoldered. But to me it seems not worth dealing with cleaning off the gel in the PCM to get at the connections. I would get a junk yard PCM.

  3. #3
    Senior Moderator CerOf's Avatar
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    I've had this happen to two ZJs.
    The one ZJ was at the dealership I worked. Was as simple as needing a new battery.

    Second one was a fuel pump.
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  4. #4

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    Quote Originally Posted by JeepDude2011 View Post
    Well I am now faced with the infamous Grand Cherokee sporadic stalling and restarting problem. Yet I am amazed by the years worth of stuff online about people with Jeeps having this exact same problem, yet there does not seem to be any surefire fix for this problem, where even the Jeep dealers can not fix this problem right away. Yet mainly I’m trying to get some answers to see what I can do myself while trying to keep from tossing tons of money senselessly at this problem. I would like to explore a few do-it-yourself options before taking it to my mechanic, because he may charge me a fortune to try to find the problem by trial-and-error . . . which worries me, since I read of so many people saying that the Jeep dealer could not readily find out this same old stalling and starting problem that seems to have plagued Jeep Grand Cherokees for many years.

    I have a 1996 Jeep Grand Cherokee Limited, with a 4.0 6 cylinder engine, with 2 wheel drive, and with about 165,000 miles.

    Upon reading about this problem in so many online forums, I was wondering what was the “one thing” that “you did” to your Jeep Grand Cherokee that fixed this problem? When I say fixed, I mean what was the “one thing” that you did that totally stopped your stalling and restarting problems for at least 6 or more months?

    To keep things easy and simple, it is not necessary to read beyond this paragraph, unless you want to know some of the background of my particular situation and problems. Mainly I am only looking for the “one thing” that "you did" that totally stopped your stalling and restarting problems for at least 6 or more months, so I can start experimenting with those solutions to see if I can quickly fix my stalling and restarting problems.

    Thank you.


    If you want to know more background on my problem, here it is:

    I have the classic case of my Jeep is unpredictable, in regards to the stalling and starting problems. The engine tends to bucks at least 3 or 4 times upon driving it for 5 to 6 days. The engine now dies within 15 to 25 minutes of driving it . . . sometimes it will start right back up or at times, it will take 1 to 5 minutes to restart it. Yet if I dare park it (after driving 15 to 25 minutes), it is a 50/50 chance that it will restart. If it doesn’t restart, it will take about 2 to 3 hours before it will start. Yet it amazes me that I can try starting the engine to the point of draining the battery down and the engine will not turn over, yet if I leave it sit for 2 to 3 hours, it quickly starts right up with no hesitation.

    Though the CEL has not been on in over 4 months, my mechanic said it only had one code, and the code was a PO138 Oxygen Sensor / Bank 1 Sensor, which he said would not be related to the stalling and starting problem. He said that he thinks the problem is electrical or it could be the fuel pump.

    I had heard that adjusting some screws by the PCM (behind the coolant reservoir) fixes this problem.

    I had heard that the CEL reader should pick up a code “11" (no crank shaft signal position signal detected), then once you replace the crank shaft sensor, this fixes this problem (I do not have this code reading).

    I have also heard that by replacing various sensors, this stopped this problem.

    I had heard that replacing the PCM fixes this problem. I wonder can I get a PCM from a salvage yard? I sure don’t want to buy a brand new PCM and it turns out that is not the problem, because I have heard of several people buying brand new PCM (for $200+) from the Jeep dealer only to discover that did not fix their stalling and starting problem.

    Yet all-in-all, it sounds like trying to fix this problem could be just about anything and that I just should be prepared to throw out lots of money trying all of these various options until the problem is fixed. Yet I'm just trying to avoid this, since I'm living on a very tight income and budget (due to our poor economy) and I can't afford to get another vehicle at this time.
    when mine was that bad i had the ignition coil replaced and from the engine jumpin weird while friving i beleve is from that and durty oil tank, clean fuel pump and replace oil filter

  5. #5
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    When I had my intermittant stalling issue while driving it was my fuel filter. Prior to that I replaced my CPS but that didn't help.

    Did the fuel filter & everthing was good until my Fule pump went out a year and a half later. New ebay AC delco pump for $130 and it's been great for the last 4 years.
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  6. #6

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    Thank you, Everyone. I greatly appreciate your help. I apologize for taking so long to get back in contact with you. I had a death in my family since I made my first post and I’m also dealing with an elderly family member who is going through some rough health issues at the moment. Now that things have settled back down again, I’m back online to work on my engine issues once again.

    Lustra, I’m going to try a few other cheaper suggestions first, then if those fail, then I will work my way into trying out more expensive options. Yet I’m glad that getting another PCM from a junk yard might work.

    CerOf, I cleaned the battery cables and put in a brand new battery almost 2 months ago, I also put in a new fuel filter, and the stalling and restarting problem still persists. Yet my problem seems to only happen when starting from a cold engine, it will heat up to a certain point and then sporadically stall and then start having restarting problems. Again, the engine dies within 15 to 25 minutes of driving it . . . sometimes it will start right back up or at times, it will take 1 to 5 minutes to restart it. Yet if I dare park it (after driving 15 to 25 minutes), it is a 50/50 chance that it will restart. If it doesn’t restart, it will take about 2 to 3 hours before it will start. The key thing I am noticing with my problem, the engine has to be cold AND had been running for at least 15 to 25 minutes before it will stall out . . . yet the engine runs fine all the time, before it stalls out.

    DiVito1012, I changed the oil and oil filter 4 weeks ago, but the problem still persists. I’ll put the ignition coil down as a possible problem and look at it later, since that will be a more costly fix.

    Eshew, I’ll put the CPS down as a possible problem and look at it later as well, since that will be a more costly fix as well, yet I want to hold off on that one for now, since I have read other people that bought “both” a brand new CPS and CPM AND replaced them, and yet that did not fix the problem.

    I will check into the fuel pump, but I will put that one my more expensive suggestion list. Is there any way that a mechanic can test a fuel pump that is bad / is going bad?

    The bottom line is, I’m going to try to see what are the free and cheap things I can try to do on my own, before taking it in to a mechanic. As I know that this is quirky problem, so I want to be able to go to the mechanic and tell him all of the things that I did on my own, otherwise I'm sure he will charge me an arm and a leg trying to find the problem and fixing it.

    Thanks again Everyone, for your help. It is greatly appreciated.

    Nick

  7. #7
    Little Brother NapsterZJ's Avatar
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    I bet you 100 bones it's the CPS sensor cause I just went through this problem.

    Buy a MOPAR sensor, ONLY! I learned the hard way. Trust me when I say this.

    hope this helps

    -2cents
    1995 ZJ Laredo 4.0 Project Never Done...Build - 5 Speed swap and 4x4 conversion - Complete
    and a stock 99 WJ

  8. #8

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    Thank you NapsterZJ. Out of all that I have read online about this problem, the CKP sensor seems like it really is the problem.

    I came across this YouTube video called Crankshaft Position (CKP) Sensor Removal. This video is 4 minutes and 7 seconds long, and this video basically tells about the problem and how this sensor is replaced. Yet my problem is, I did not get a crankshaft position code, when my codes were pulled. So I'm not sure if the engine has to had stalled out before it reads on the tester or does this code stay recorded. Yet when my Jeep was running okay (that day when I had the codes pulled), that code did not come up and nor was it stored. Yet I am going to see what I can do on my own first. Then if I can't fix the problem myself, then I'm going to get the mechanic to try to fix the problem. Yet rather than suffer at the hands of the mechanic and to stop him from searching for the problem and charging me for all of that, I think I will just start off by having him replace the CKP and then see how the engine runs first. Then if that does not fix the problem, then I will explore some of the other more costlier options.

    Nick

  9. #9

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    Quote Originally Posted by NapsterZJ View Post
    I bet you 100 bones it's the CPS sensor cause I just went through this problem.

    Buy a MOPAR sensor, ONLY! I learned the hard way. Trust me when I say this.

    hope this helps

    -2cents
    X2 ^^^^^^


    This is what I was going to suggest. Your mechanic can do a pressure and volume test on your fuel pump to check it's condition. If you haven't done so already try changing your fuel filter.

    The CPS sometimes doesn't throw a CEL. I've seen them be totally shot and not throw a CEL. If it's an problem that comes and goes this seems to be a sensor that doesn't activate the CEL.

    If you have a DVOM ( Digital Volt and Ohm Meter) check the resistance and volts across the sensor and see if it's spec. Not sure if you have access to the specs sheet or not. If the sensor is good check the harness.

    Then I would look at the fuel pressure and volume..


    James

  10. #10

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    JForestZ34, thanks for the additional feedback and help. Yes, I did change the fuel filter, shortly after the stalling problem first started, back when it always started right back up when it stalled, but that new fuel filter did not help. As time went on, things escalated to the point where it now takes longer to start and it is now much harder to start after it stalls. Yet I will have the mechanic do that pressure and volume test on my fuel pump as you suggested.

    Thanks again.

    Nick

  11. #11
    Little Brother NapsterZJ's Avatar
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    CPS, CKS, It's all the crank shaft position sensor

    You most likely won't get a code because it just straight up stalls.

    My my stuff was acting up, my ZJ would get up to operating temperature, get an extra 10 minutes of driving then flat out 0 rpms like the car goes numb. I checked to get any codes...none, let it cool off, and started it right up again.
    1995 ZJ Laredo 4.0 Project Never Done...Build - 5 Speed swap and 4x4 conversion - Complete
    and a stock 99 WJ

  12. #12

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    Quote Originally Posted by Nick_S View Post
    JForestZ34, thanks for the additional feedback and help. Yes, I did change the fuel filter, shortly after the stalling problem first started, back when it always started right back up when it stalled, but that new fuel filter did not help. As time went on, things escalated to the point where it now takes longer to start and it is now much harder to start after it stalls. Yet I will have the mechanic do that pressure and volume test on my fuel pump as you suggested.

    Thanks again.

    Nick

    If you have a good mechanic when he does the pressure and volume test on the fuel pump hopefully he will do a residual fuel pressure test. That test is done to check fuel pressure after you turn the key off. If your residual pressure check valve is bad in your fuel pump it will cause your fuel pressure to bleed off after you shut the car off. That will cause hard starting. Either that or you have a leaking fuel injector. But you mechanic will test for that also.


    James

  13. #13

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    NapsterZJ, thank you for more feedback. I’m going to pose another question (in about 2 hours of this post) in a new thread titled “Is it my CPS or PCM?” Mainly since people have made many comments of the stalling and starting warm to hot engine problem, in some cases one or the other is the sole problem. So I am just wandering is there any easy way to find out which one is the actual problem.

    JForestZ34, thank you. For sure, I’ll have the mechanic do a pressure volume test (for the fuel pump), along with a residual fuel pressure test as well. Now one thing is, when my engine is running normally, I never have any trouble starting it. I can leave it sit in the garage for a week or two, and it always instantly starts up. The stalling and restarting problems solely seem connected to the engine being warm or hot. Because I have done mini-trips, where I can drive to and park at maybe 3 locations (within 15 to 25 minutes), without the engine stalling, while the engine instantly & easily starts right up . In this situation, I can park, turn off the engine, let it set for a few minutes, then start it right back up again with the utmost of ease (in this 15 to 25 minute window). Yet nowadays, once that engine has been running for at least 15 to 25 minutes (consecutively or broken up), the engine WILL stall at some point (driving it within 15 more minutes). Yet when the engine dies in mid-drive, it will either start right back up or it will take about 1 to 5 minutes to restart it. Other than one time (last summer) where it died in the middle of traffic and would not restart after 15 minutes of trying, that was the only time that I could not get it restarted (in about 1 to 5 minutes). Whereas as long as it is in mid-drive when it stalls, it always will restart within 1 to 5 minutes, whereas whenever I park after driving it 15 to 25 minutes, that is where the 50/50 restarting challenge comes in. Yet what amazes me is, when it will not restart (in this case, while parked), is that I can sit there for 15 minutes trying to restart the engine and it WILL NOT START. Yet once I leave it sit for 2 to 3 hours, as soon as I try to restart it, it starts up so quick and fast on just a half of a key turn 99% of the time. So my problem mimics NapsterZ'sJ problem. So something seems to definitely cause the engine to stall and have restarting problems once that engine heats up to some degree.

    Nick

  14. #14

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    As I work on my lists of things that I need to check for my stalling and restarting problem, I was wondering, does the “MAP sensor” or “camshaft position sensor” might have any major part in this stalling and restarting issue? Thus far, it seems the major players for this problem that I have most read about is the “PCM” and “CPS”. Yet I’m not sure if a “camshaft position sensor” and a “crankshaft position sensor” are one in the same or are they 2 different sensors.

    Lastly, one recommendation I had read was to “clean the throttle body and IAC”, yet I’m wondering could this be related to the infamous stalling and restarting issue as well?

    Your thoughts?

  15. #15

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    Hello Everyone,

    Here is my update as of yesterday (04-21-12), on this problem. After taking a couple of weeks (during my free time), I tried to locate the problem(s) myself . . . based on all of the EXCELLENT & AWESOME advice, feedback and the many suggestions that I received from this form and a few other online auto repair forums. However I was unable to find any problems on my own.

    Yesterday, I took my Jeep into a new local ma-and-pa garage (that I wanted to try out), just to get an engine diagnostic done. I made sure that I had warmed up the engine for about 30 minutes beforehand, while hoping that it did not stall out on me on the way to the garage. Once the mechanic hooked it up to the machine, then about 15 minutes of running the diagnostics, the “crankshaft position sensor” was the only problem that came up.

    Since I had made it this far, I inquired about the “ignition coil”, the “CPS”, and the “fuel pump”. In this case, the mechanic told me that those 3 parts were fine as far as he could see ALONG with what the diagnostics was telling him, ALONG with him taking time out to explain why he “personally” believed that none of those other 3 parts were a problem.

    So I gave him the okay to swap-out the CPS. Yet once he swapped-out the CPS, he ran into trouble syncing it to the CAMshaft Position Sensor (an old part) to the CPS (a new part) “so he claimed”. So he had to install a new CAMshaft Position Sensor (also known as a “sync pulse generator”, which I’m guessing is the ring thing under the distributor cap). Now with that being said, I am hoping and praying that is the end of this nightmare. Yet I will give you an update in about 2 or 4 weeks, as I want to get some miles on these 2 new parts and report back.

    Yet in my case, since I am a sub-novice, when it comes to auto repairs, I would highly recommend to anyone in my category (sub-novice), that if any of you have this infamous stalling and restarting problem, I would HIGHLY recommend that you take your Jeep to a mechanic and have him/her do an engine diagnostics first (before trying to guess and throw parts at this problem) AND always make sure you address the 4 usual suspects in this problem . . . the “ignition coil”, the “CPS”, the “PCM”, and the “fuel pump”. In the event you have to eliminate these 4 parts, then you can look for other potential causes for this problem. Yet based on my reading on this problem for about 1 ½ months, these seem to be the 4 parts you should always check-out first, before doing anything else.

    Most of all, I can not begin to thank all of you who were so kind and generous to take the time to help me. I sincerely and greatly appreciate all that you have done for me, and I hope that my thread helps others who come to this forum in the future, seeking help for this exact problem. For sure, having this quirky problem has been at least 100 times worse than riding a white-knuckler roller coaster ride! I think the 3 scariest times that I had to endure and got more gray hairs from was the 2 times that the engine stalled while I was in mid-drive while on the freeway doing at least 70 mph AND having someone behind me about 2 car lengths. GASP!!! Thank GOD and thank to quick thinking, I was able to throw it into neutral AND it quickly started back up AND I was able to throw it back into “drive” and keep moving. I ALMOST needed to change my shorts when I got home that day. UGH!!! Yet after the second time that it stalled on the freeway, I stopped driving on the freeway, because I did not want to take any more crazy chances with this problem on the freeways. Then the 3rd scary encounter happened one day when I was sitting at a red light (I was the first guy in the front of the line, in the fast lane). It must have been about 5 to 8 cars behind me . . . because it was a long red light. Then when the light turned green, I took off and was getting up to almost 35 mph AND the engine stalled AND it would not restart right away (and I threw on my emergency flashers). GASP!!! Needless to say, the car behind me was almost on my tail when we took off AND it really was a miracle that this guy did not slam right into the back of me. WHEW!!! Yet as I was trying to restart the engine, I could see all of the people getting from behind me. Yet I won’t mention the countless times that my Jeep stalled out in the middle of traffic and would not restart right away WHILE I made many wonderful new traffic friends, as they got from behind me blowing their horns, with angry faces as they drove past me, sometimes waving their fists at me . . . and sometimes giving me the bird. Had I known that getting a Jeep would have helped me make so many great new friends quickly, I would have purchased a Jeep years ago! LOL!!!

    One maddening thing is, for the past 3 weeks, I have driven my Jeep for at least 15 to 25 minutes, and it would either stall or would not restart (until it cooled down at least 2 to 3 hours). Yesterday, I went driving around trying to hope that it would stall, so I could at least try to use the code reader to get a code to take to the mechanic (if it threw a code when it stalled). However I could not get the engine to stall, so I never had a chance to see what would happen when it stalled and if it “would” or “would not” throw a code or a CEL. After letting it sit for about an hour, I tried to re-start it 4 times during that hour, and the engine started up right away. Since the stalling and restarting problem ONLY happens when the engine is warm or cold, I purposely parked my Jeep in my drive way and let the engine run for 30 minutes (as I wanted that engine HOT when I took it to the mechanic). So after the engine being warmed up for 30 minutes, I drove it to the garage, about 1 mile from my house. The engine ran fine, did not stall. Since I got to the garage before it opened, I figured this would be even better, because once the engine is warm or hot, it ALWAYS would not restart after sitting for 5 or more minutes. So 15 minutes later, the mechanic came to open the garage. So I tried to start the engine, and that SON OF A BISCUIT engine started up like there was nothing ever wrong with it. GRRRRR!!! It was as if the engine said, “I’m going to make a lier out of you, while I get the upper hand.” Well folks, I will say one thing, Murphy’s Law is alive and well in my Jeep . . . i.e. You can experience hundreds of problems with your vehicle while you are not in front of your mechanic (these problems can go on for days, weeks, months, years), YET as soon as you take it to a mechanic the vehicle runs perfectly fine AND WILL NOT duplicate ANY problem you had with it while away from the mechanic. LOL!!! Yet this problem is very sporadic and you get no warning when it will stall or when it is about to stall, and nor do you get a warning when it decides that it is not going to restart. Yet hopefully, by getting an engine diagnostics done, the mechanic will be able to tell you what part(s) are bad, that way you don’t have to guess and start throwing parts at your engine until the problem is fixed. Yet when I was ready to get a mechanic's help, I needed to first find out if any of the 4 usual suspect parts were bad. So luckily today, the mechanic told me that it was the “CPS” that was the problem and not the “ignition coil”. Yet as a sub-novice, I could not test any of these 4 parts on my own, I needed the mechanic to do it. Yet reading these online forums can only help a sub-novice so much, because in most cases, the BIG GUNS (getting a mechanic that can see and touch the engine to tell you what "might be" or "what is" wrong) will have to come out. Yet I really do think that my Jeep is possessed. LOL!!!

    All-in-all, I would not wish this infamous Jeep Grand Cherokee stalling and restarting problem on my own worse enemy! : - )

    Nick

  16. #16

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    I too feel the frustration regarding some of the fixes for these issues. I was always amazed at how many people say things like "change the air filter" or "add some gas treatment." I went through this with my 6cyl 96 ZJ 8 months ago. The one thing that fixed it was a new PCM from autozone. I zip stripped the plugs to the new PCM to ensure they stayed tight. 20,000 miles later, no issues. A bad CPS can/will cause the same issues though. And people are right when they say to use Mopar sensors. They are more reliable. FWIW, I have never witnessed a fuel pump that "kind of goes bad". They either work or they dont. If you turn on the ignition and hear the whine from the gas tank, the pump works. In addition, I do all my own work and let me tell you, these damn ZJ's seem to have 3x the issues my WJ has. Got to love em or find something else.

  17. #17
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    Quote Originally Posted by Nick_S View Post
    Hello Everyone,

    Here is my update as of yesterday (04-21-12), on this problem. After taking a couple of weeks (during my free time), I tried to locate the problem(s) myself . . . based on all of the EXCELLENT & AWESOME advice, feedback and the many suggestions that I received from this form and a few other online auto repair forums. However I was unable to find any problems on my own.

    Yesterday, I took my Jeep into a new local ma-and-pa garage (that I wanted to try out), just to get an engine diagnostic done. I made sure that I had warmed up the engine for about 30 minutes beforehand, while hoping that it did not stall out on me on the way to the garage. Once the mechanic hooked it up to the machine, then about 15 minutes of running the diagnostics, the “crankshaft position sensor” was the only problem that came up.

    Since I had made it this far, I inquired about the “ignition coil”, the “CPS”, and the “fuel pump”. In this case, the mechanic told me that those 3 parts were fine as far as he could see ALONG with what the diagnostics was telling him, ALONG with him taking time out to explain why he “personally” believed that none of those other 3 parts were a problem.

    So I gave him the okay to swap-out the CPS. Yet once he swapped-out the CPS, he ran into trouble syncing it to the CAMshaft Position Sensor (an old part) to the CPS (a new part) “so he claimed”. So he had to install a new CAMshaft Position Sensor (also known as a “sync pulse generator”, which I’m guessing is the ring thing under the distributor cap). Now with that being said, I am hoping and praying that is the end of this nightmare. Yet I will give you an update in about 2 or 4 weeks, as I want to get some miles on these 2 new parts and report back.

    Yet in my case, since I am a sub-novice, when it comes to auto repairs, I would highly recommend to anyone in my category (sub-novice), that if any of you have this infamous stalling and restarting problem, I would HIGHLY recommend that you take your Jeep to a mechanic and have him/her do an engine diagnostics first (before trying to guess and throw parts at this problem) AND always make sure you address the 4 usual suspects in this problem . . . the “ignition coil”, the “CPS”, the “PCM”, and the “fuel pump”. In the event you have to eliminate these 4 parts, then you can look for other potential causes for this problem. Yet based on my reading on this problem for about 1 ½ months, these seem to be the 4 parts you should always check-out first, before doing anything else.

    Most of all, I can not begin to thank all of you who were so kind and generous to take the time to help me. I sincerely and greatly appreciate all that you have done for me, and I hope that my thread helps others who come to this forum in the future, seeking help for this exact problem. For sure, having this quirky problem has been at least 100 times worse than riding a white-knuckler roller coaster ride! I think the 3 scariest times that I had to endure and got more gray hairs from was the 2 times that the engine stalled while I was in mid-drive while on the freeway doing at least 70 mph AND having someone behind me about 2 car lengths. GASP!!! Thank GOD and thank to quick thinking, I was able to throw it into neutral AND it quickly started back up AND I was able to throw it back into “drive” and keep moving. I ALMOST needed to change my shorts when I got home that day. UGH!!! Yet after the second time that it stalled on the freeway, I stopped driving on the freeway, because I did not want to take any more crazy chances with this problem on the freeways. Then the 3rd scary encounter happened one day when I was sitting at a red light (I was the first guy in the front of the line, in the fast lane). It must have been about 5 to 8 cars behind me . . . because it was a long red light. Then when the light turned green, I took off and was getting up to almost 35 mph AND the engine stalled AND it would not restart right away (and I threw on my emergency flashers). GASP!!! Needless to say, the car behind me was almost on my tail when we took off AND it really was a miracle that this guy did not slam right into the back of me. WHEW!!! Yet as I was trying to restart the engine, I could see all of the people getting from behind me. Yet I won’t mention the countless times that my Jeep stalled out in the middle of traffic and would not restart right away WHILE I made many wonderful new traffic friends, as they got from behind me blowing their horns, with angry faces as they drove past me, sometimes waving their fists at me . . . and sometimes giving me the bird. Had I known that getting a Jeep would have helped me make so many great new friends quickly, I would have purchased a Jeep years ago! LOL!!!

    One maddening thing is, for the past 3 weeks, I have driven my Jeep for at least 15 to 25 minutes, and it would either stall or would not restart (until it cooled down at least 2 to 3 hours). Yesterday, I went driving around trying to hope that it would stall, so I could at least try to use the code reader to get a code to take to the mechanic (if it threw a code when it stalled). However I could not get the engine to stall, so I never had a chance to see what would happen when it stalled and if it “would” or “would not” throw a code or a CEL. After letting it sit for about an hour, I tried to re-start it 4 times during that hour, and the engine started up right away. Since the stalling and restarting problem ONLY happens when the engine is warm or cold, I purposely parked my Jeep in my drive way and let the engine run for 30 minutes (as I wanted that engine HOT when I took it to the mechanic). So after the engine being warmed up for 30 minutes, I drove it to the garage, about 1 mile from my house. The engine ran fine, did not stall. Since I got to the garage before it opened, I figured this would be even better, because once the engine is warm or hot, it ALWAYS would not restart after sitting for 5 or more minutes. So 15 minutes later, the mechanic came to open the garage. So I tried to start the engine, and that SON OF A BISCUIT engine started up like there was nothing ever wrong with it. GRRRRR!!! It was as if the engine said, “I’m going to make a lier out of you, while I get the upper hand.” Well folks, I will say one thing, Murphy’s Law is alive and well in my Jeep . . . i.e. You can experience hundreds of problems with your vehicle while you are not in front of your mechanic (these problems can go on for days, weeks, months, years), YET as soon as you take it to a mechanic the vehicle runs perfectly fine AND WILL NOT duplicate ANY problem you had with it while away from the mechanic. LOL!!! Yet this problem is very sporadic and you get no warning when it will stall or when it is about to stall, and nor do you get a warning when it decides that it is not going to restart. Yet hopefully, by getting an engine diagnostics done, the mechanic will be able to tell you what part(s) are bad, that way you don’t have to guess and start throwing parts at your engine until the problem is fixed. Yet when I was ready to get a mechanic's help, I needed to first find out if any of the 4 usual suspect parts were bad. So luckily today, the mechanic told me that it was the “CPS” that was the problem and not the “ignition coil”. Yet as a sub-novice, I could not test any of these 4 parts on my own, I needed the mechanic to do it. Yet reading these online forums can only help a sub-novice so much, because in most cases, the BIG GUNS (getting a mechanic that can see and touch the engine to tell you what "might be" or "what is" wrong) will have to come out. Yet I really do think that my Jeep is possessed. LOL!!!

    All-in-all, I would not wish this infamous Jeep Grand Cherokee stalling and restarting problem on my own worse enemy! : - )

    Nick
    Kills me when Aholes behind me are right on my bumper no matter how fast I'm going.
    2002 Grand Cherokee Laredo 4x4 4.0 - Stock

  18. #18
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    Nov 2006
    Location
    Markham, ON, Canada
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    I read somewhere that some PCM's short out around the mounting screws for some reason. You could try backing out the screws a 1/4 turn or so and see if that does anything for you. Its a weird problem for sure.
    This costs nothing. Maybe disconnecting the -ve battery terminal first then reconnecting when done.

    Good Luck

    2002 Grand Cherokee Laredo WJ 4x4 283,000km Jan. 2014
    I6 4.0, Transmission Cooler
    Class III In-Bumper hitch
    Westin Safari Light Bar w/big amber driving lights
    Nokian WR SUV All Weather Plus 245P70R/16 - retired due to wear
    Yokohama Geolandar I/T 245P75R/16 on it now. Winter 2014

    2009 Jeep Compass 4x4 North Edition, 2.4L, CVT
    101,000km
    Many problems with the Compass - DON'T BUY CHRYSLER JUNK

    Nokian WRG2 tires (poor wear, cup easy and real noisy now)
    Markham, ON
    Canada

  19. #19
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    Apr 2011
    Location
    Golden Horseshoe
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    215

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    To test the PCM simply get some long zip ties and zip tie the PCM connectors to the PCM. This will help stop the PCM connectors from moving resulting in no more or less stalling. You don't need to back out any of the screws, if the PCM was shorting out, it would pop fuses and or stop working altogether, that's just noob.


  20. #20
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    Nov 2006
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    Markham, ON, Canada
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    Quote Originally Posted by Lustra View Post
    To test the PCM simply get some long zip ties and zip tie the PCM connectors to the PCM. This will help stop the PCM connectors from moving resulting in no more or less stalling. You don't need to back out any of the screws, if the PCM was shorting out, it would pop fuses and or stop working altogether, that's just noob.

    http://forums.cnet.com/7723-7811_102...talling-fixed/


    2002 Grand Cherokee Laredo WJ 4x4 283,000km Jan. 2014
    I6 4.0, Transmission Cooler
    Class III In-Bumper hitch
    Westin Safari Light Bar w/big amber driving lights
    Nokian WR SUV All Weather Plus 245P70R/16 - retired due to wear
    Yokohama Geolandar I/T 245P75R/16 on it now. Winter 2014

    2009 Jeep Compass 4x4 North Edition, 2.4L, CVT
    101,000km
    Many problems with the Compass - DON'T BUY CHRYSLER JUNK

    Nokian WRG2 tires (poor wear, cup easy and real noisy now)
    Markham, ON
    Canada

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