I Wiggled my PCM Connectors while running, and as I wiggled it, the jeep would start to die, and come back to life. Loose connection at PCM connector, wires pressed up against frame. Went from rough starts,stalls,misfires, to perfect driving jeep. 98 Grand Cherokee Laredo 4.0 inline 6
Glad it worked for you. What we jeep enthusiasts need to remember is that we need to troubleshoot first and foremost. There's also a ton of RU-vid videos that have helped me personally to troubleshoot problems with my jeeps. Keep the information flowing. Good luck and happy jeeping.
Mine did i last summer i cleaned the iac valve behind the air intake. 2 screws i pulled it out used a little degreaser and a q tip to get in there it made a huge difference. I have a 97 grand cherooke laredo 5.2.
Venom.... you are the man!! I have been going crazy trying to.figure out what is wrong with my 98 jeep grand Cherokee lorado it's been stalling and acting funny for about 2 months. I got a multi meter and soldering iron from harbor freight watched your video and fixed my car! It has now been 4 days and still not stalling out! Was happening constantly everyday. Thank you your the man!!
Is there a video for doing g this I am now having g this problem changed everything I wiggled the pcm and shut the truck off so it's gotta be its a 98 just don't wanna mess it up
I currently own 23 Jeep XJs and WJs and you hit the nail on the head! We have been doing this for a few years now on our Jeeps, just be careful in the pre-OBD II models built prior to 1996. Those don't have the same PCM and the configuration is different inside. The 1996 through 1998 PCM is the same and your fix will work like a charm on a number of issues that crop up. The PCM built from 1992 (The first official production run says 1993, but the PCM was built in mid 1992) until 1995 are OBD I technology and are limited in scope. These older PCMs can't effect the engine operation as much and usually just cause the Jeep not to start. Good video!
RC Trucks Jacksonville is this also tied into xj dying while they are turning right? Every time I take a sweeping right turn it’ll cut out unless I give it throttle. I’ve filled the tank full to no effect so I’m a little lost now. I cleaned all my grounds and tightened box mounts. What’s next? Clean the pcm like he’s talking? 1997 xj sport
I have the same problem with my 97 Jeep GC. I installed a remanufactured PMC and the Jeep stopped stalling for three years.. and now I have crank with no start.... good thing that I have a lifetime warranty for the PCM
Thanks!! Finally someone who knows what’s going on. Why hasn’t Jeep done a warranty on this, it seems most jeeps are having this problem, my 2004 just started to stall, and I’m nyc traffic it’s not fun.
So I have an 02, and mine has been doing it for months, I’ve replaced every sensor on the throttle body, and the TPS, and the crank sensor, and the cam synchronizer... been searching for a video that is right, been dumping money time and parts into it. Did it fix yours, and did you get an OEM version
nothing lasts forever, the manufacturers only have to warranty a vehicle for the period set when you bought the vehicle and they only have to provide parts to sell you for a vehicle for 7 years. expecting anything to last forever is a bit naive of anyone to expect.
My '99 Laredo goes for 6 months without stalling or no starting (no sputtering), after when it stalls or won't start, I just grab and shake the ECM and wiggle the wires at the ECM and off I go. But when it does happen, it happens a number of times in one day, lasts for a couple days. But then as I said, will go for a lengthy time with no problems. It's very irritating.
Just a FYI/PSA. If your high milage jeep distributor is the original part off the assembly line. Do your jeep a favor and replace it. I have 209k on my original and of course it began chirping. Only figured this out while trouble shooting random(when @ norm temp) stalling issue. Pulled the distributor, aside from the wear of the gears/oil pump drive. I could hardly rotate the shaft by hand. My stalling issue was cause by the crankshaft position sensor (CKP). I install a sensor from the dealership. Trust no other when dealing with sensors.
I just removed the 2 1/2" torks head screws below the plugs on the pcm and shortened them down to 1/4" and put them back in. Absolutely no problems at all.
Steve, What was the Jeep doing when you shortened the screws? I have a 2001 Jeep Cherokee XJ and it just had a engine installed in it a month or so ago. Idle is rough. Starts but then quickly stalls out. Battery is charged. Alternator is good. Wondering if my problem is the PCM, crank position sensor or cam position sensor. I have checked the grounds. All are clean.
I just looked at my PCM, there is a re call sticker on it and still has this same issue, @ Matt Leopold Id call the dealer see if there is a recall. I saw another video where the guy used shorter screws that hold the PCM to the metal bracket(that holds it in place), the guy said it fixed the issue. on mine it looked like the Molex plug towards the engine, doesn't have a MOLEX LOCK on it. So I re seated it but if it still happens, I'll try the other trick I mentioned. Mine only happens after the engine warms up..........
We appreciate your effort with Trying to Tell Me What to Do I’m having Computer or immobilizer this makes the third time the antitheft immobilizer or pcm whatever you call it has hung me up away from home it’s always been the fuel pump being shut off and I had a fuse tap from cigarette lighter fuse to fuel pump fuse and it been working fine until a week ago it done the same thing again but this time It was unable to use a fuse tap also my windows aren’t working and the transmission want shift into high gear and the radio want come on plus fuel pump not working so I ran a wire from fuse in dash to fuel pump positive wire and it started I drove it home 70 miles in low gear 45 mph it would run faster but it had rpm’s at 4.5 I just wish I could see what it is that You Are Trying to show us you did! I ain’t trying to come across Ugly sir I really can’t see what you’re doing and exactly where it’s located and all that. I have a 2005 Jeep Grand Cherokee 3.7 two wheel drive
Hello Lucidvenom, I have a 99 Grand cherokee 4.7 v8 w/same issues I replaced a bunch of things: all 8 coils sparkplugs idle sensor air control valve and same idle rough & up & down RPM as I go to stop. I will do this pcm and see what happens QUESTION I have is: since I have "engine light on at all timeswill that main brain maybe throwing this codes arbitrary? You may think? Regards Pete
Could a bad PCM (computer) cause a battery to bubble or over change the battery? I have a 2000 Jeep Grand Cherokee 4.7 V8 and i replaced my fuel pump, fuel filter, spark plugs, crankshaft sensor, camshaft sensor, oil pressure sensor, battery terminals, and I've gone through 3 battery within 1 1/2 months... I was looking for loose connections or bad ground wires, but i couldnt find anything.. I was thinking about opening my PCM up and check for connectivity. Then if I have to solder the connections. Please let me know what u think.. Thanks.. Good video by the way... I seen the other video on the inside look of the PCM.. Also good video..
It's not always the pcm, my 99 4.7 wj was stalling for a while even while or shifting hard while driving , I replaced the map and tps and I haven't stalled once
I did the soldering like a year and a half ago...it didn't work. Im probly gonna try trimming the screws next. ..but this jeep doesn't get a lot of use anymore, so im not in a big hurry.
One day I was drinking home from work, my jeep just went off, luckily I was not driving on the freeway. I remember the Jeep lightly jerking, slightly shivering for amount, the rpm dip a little. That was scary
My 98 backfired and blew out the Metal housing of my muffler. I don't know why it wouldn't have went out the tailpipe instead. It looked & felt as though someone put a stick of Dynamite in my muffler.
It turns out due to a faulty PCM ,the mix was so rich that fuel actually collected at the bottom of the muffler, once the muffler got hot enough it ignited the fuel that had pooled at the bottom causing an explosion.
I have a 96 Jeep Grand Cherokee Laredo once it gets above 50 degrees outside it will not start I have change the crankshaft positioning sensor distributor ignition coil and ignition switch I'm thinking it's the PCM any ideas has anyone had this problem before
it's the jeep's brain, when the contacts inside wear out where the factory solders them on usually the computer is rated for 100-120k miles, beyond that the computer most likely needs replaced. you can just remove the overflow tank and put it out of the way with the hose still on, turn the car on then just widdle the 3 big connectors on that PCM, if the car starts stuttering or dies it is 100% your PCM. i had this issue, and i could drive hundreds of miles and it not stall, or one bump would make me roadside. NOTE: temp fix is wrapping a zip die over the top and bottom of the 3 connectors, the zip ties will push the connectors against the inner parts of the PCM and this can save you from needing a tow-truck. JEEP RULE, always have zip ties =) and the Crank Position Sensor can also give the same exact symptoms. i recommend NOT opening your PCM as it can, and will worsen the problem if the PCM is causing the issue. check PCM first before crank position sensor.
i have a 1998 jeep grand Cherokee and i got a reader thing and it kept throwing the code for a new CPS. i replaced it, and it runs for a few minutes and then when i seems to warm up (or after idling for a few minutes) its dies out. and then it wont start up again..do you think this would solve the problem of it not starting?
I have a similar problem with my liberty instrument cluster. Dials are dead, but the other warning lights all work. I used to get weird random charging problems/stalling too. I'm going to take a look at the PCM now. Did you remove it completely to fix it? Thanks
My 95 Jeep Cherokee stalls out in hot weather. Why only in hot weather does the problem surface? Won't restart until about 20 minutes. Cold and cool weather is no problem. Mechanic says PCM issue, but he didn't test for code. I don't want to spend $300 and risk that it could be something else.
well if your check engine light is on got to auto zone and have them run a check for codes if not grab a same model and engine and year pcm from a junk yard for a fraction of the price
Frank Cavallaro Its your crank sensor back of the motor on top of the bell housing, 20 bucks but you will need like 6 extentions with a 10mm socket to get it out, good luck
I have a 2000 Jeep Grand Cherokee Laredo, new crankshaft position sensor, still hard to crank and stalling/dying at red lights. Before it went in the shop I noticed a little static and cutting out on the radio as well. Repair shop said definitely a computer problem. Two questions.. when looking on line, i see the computer refered to as pcm/ecm/ecu.. are these all the same thing? Also, repair guy told us that the jeep wouldn't run with a new computer unless we take it to the factory and have the computer reset there because of the anti-theft system, i see they are advertised as plug and play on ebay with no additional programming needed. Can you recommend a place to purchase and tell me if the anti-theft system would really require extra programming?
@rachel. Where you able to find the right pcm and which did you order? Did you have to go to dealer? Did you try the video fix fix? I'm having same issue w my 96 grand Cherokee. Radio cuts out too. Guessing I have same pcm issue.
I have the same problem I changed the crank position sensor which i thought it was the car is stalling and sputtering but didnt do anything ,but am going to attempt the soldering pcm connections it seems to be a common problem with this type of vehicle.
Mine stalls sometimes after a while of driving...replace pcm?...an when i got it had someone put a 04 ecu in it cause the ignition switch was bad..maybe replace the ignition switch an put new pcm in it??? Help me out here lol
I have a Jeep Grand Cherokee 2003. On high revs, as when picking up speed, when overtaking or going up a steep incline, a noise will come from the undercarriage and the engine light will come on. In slow traffic and engine idling the engine light comes on and the vehicle may stall. Please, can anyone give me an idea what could be causing this problem ?
I bought a brand new PCM and had it programmed to my vin and everything and it ran fine for all of one afternoon and at night when I came home from work it did the same damn thing again cuts off and won’t restart her I have an hour but keeps wanting to cut off it’s a brand new PCM what the hell?
I just found the wires going to the front 02 sensor where all melted and causing the asd to engage and blow the fuse so you might want to check the wires that are associated with the automatic shut down relay I had went around the corner and it wouldn’t come back on again check your fuses underneath the hood of the car if you have a middle one that’s a 20 amp blown start checking the stuff that is associated with that relay and you may find wires that are bare like I did
on I got the same jeep even the same color but a 98 it happens to do every thing your jeep have done now what part am I needing to replace to fix the problem?
The 98-04 have mainly the same components, snd this comment is 4 years old so I imagine you fixed it... or junked it, but if you fixed it, did the PCM fix it? Haha
i have the same jeep same year and it does the same thing, and i got a p0351 code, so do is it cheap to replace? i already poured a lot of money thinking it was something else
96 jeep grand Cherokee laredo. im haveing the same problem. my engine light is on. when the pcm is hot my car wont work. but when its cold it runs till it gets hot. this is my 2nd pcm thats doing it. please hit me up so i can go into further details. iv done so much to that car that im to much into it.
I removed the bcm and it was just one screw holding a large plug on the front. after I removed the bcm I opened it and the idk motherboard is encased in jelly. so I'm not sure a 95 grand Cherokee Laredo 5.3 has the same thing.
I've watched the video over and over and still don't know what you mean by connectivity? I understand the word, but do not know what is supposed to show connectivity and from where to where?
I have a 98 and the wires that plug in the computer if I move it and put cardboard it will run but it gets lose and shuts . So you think it needz to be solider .. could use some help if you can !
check the computer connections shown in my inside look video. and a quick fix after that is zip tie the connector to the computer so it wont come loose.. best of luck to ya
have a jeep grand cherokee laredo 97 and she has a defect that nois not cosegue solves .You are swimming norml suddenly she comessa to fail and popcorn, already fis nozzle cleanup already switched fuel pump already fis everything and concigo solve the problem. and the problem will and vouta's nothing you can give me a hint of what can be .sou here you bear the Brazil ja I am grateful.
so a new pcm fixes this too? I can't Sauder anything.. but my jeep is currently in the shop. they called and said I need a pcm but they have to dig farther into it to be certain. if the computer is that close why are they taking two hours to pull out the computer
I have a 2001 JGC, the truck start's fine, i go in reverse fine then when i shift into drive'the truck shakes and shuts off or it'll shake and i take my foot off the brakes and it'll stay on but sputters for a few seconds, is it the same issue?
Same exact thing happens with my 94 zj. Cold start is fine. I let the it warm up for about 5 min. Put it in gear and it does what u describe. So I usually put it in neutral and it calms down then back in gear then off I go.
Ok i have a question i just got my jeep up and running new ignition and everything but it stalls right after it starts would this fix it btw i didnt even put a whole gallon of gas in it lol let me know if this could be my issue
I have a 1998 jeep grand Cherokee. watched the video of the brain but mine is different than what I have found on the fix of the brain. so is there anyone else know of the different brain how to fix this kind ? the part number for this type brain is 5 15 AB need help.. thanks
I'm having same issue and its driving me crazy I fill it up with grease it runs till next day and messes up again. Question for you is it the main screws holding the PC to the firewall or the ones on front of the pcm?
I have a 99 grand cherokee laredo. Anytime I step on the gas rpm's fall and alot times stalls. Starts rough, usually at least 2 times till she starts. I got codes po 171 and po 174. Replaced coil and plugs, fuel filter. I have to do a fuel pressure test. Anyone with any advice please help
So fuel pressure read 18-21 psi. Was a slight leak near the gauge so I doubled it and still was shy of the 44-54 psi range. Changing out the fuel pump since the fuel filter was done last week. I'll post if the issue is resolved. I'm signing up for jeepforum
The leak was from the tester, thats what I get from going cheap. If was barely dribbling so I'm sure I more than compensated for whatever was leaking out
You'll need a multi-tester, you can buy it at Walmart or any hard ware store. Set the dial to ohm and check for continuity. That's when the needle moves to the right from zero.
bro hit me up I would like to talk to you I just opened up my 98 Jeep Grand Cherokee PCM I solder to what I thought I could solder much as I can I'm afraid to put it back in the car lol I did get another one from eBay a month ago but now its acting up again so I put that I did the host clamp trick wrap the holes clamp around all three plugs are you still driving her did she fall apart again is a computer acting stupid again are you still driving with no problem please get back
today ii ttoook out the brain & clleeaned thee outsiide oof it & the wiirees..iit improoveed but stilll cut ooff..thee junk yard selllls brains for 27.00..tthee bold numbers on tthe stiicker are 412..are there any others that aree compatible?
I found this fix on jeepforum.com. Hope it helps. InterpreDemon I know there are several other threads here and dozens about the net regarding intermittent/random stalling and all the nightmares folks have gone through trying to kill the gremlin for good. Like others I went through the progression on on '97 4.0 GC, in the process replacing all the usual sensors and such, but as the problem progressed I became more and more convinced the problem was the PCM connections, that all the temporary fixes could be attributed to people plugging and un-plugging their PCMs. I had gotten down to the point where I knew that if I fiddled with the cables I could replicate the problem and I refused to do the "magic screw" repair or the tie-wraps because I believed both of them involved movement of the plugs and cables with temporary restoration only until such time that the cables relaxed to their normal intermittent state and the symptoms returned. Though there doubtless are situations where the PCM is really bad, I had gotten down to the point where I absolutely knew that if the PCM was not bad it MUST be the cable connections. Having disassembled a PCM I found it hard to believe that the connection pins could have or develop bad solder connections to the mother board given the hermetic sealing involved, nonetheless I decided to order a re-furb from the folks in Davie, FL to rule out the PCM prior to tearing those three plugs apart. When I got the PCM two days ago on Friday I put it in and the car refused to start... no primary ignition at all and that unit was clearly a DOA doornail. Talked to their tech, who couldn't believe it at first because they supposedly check them all before they go out, but putting my old unit back in and starting right up in a flooded state confirmed the kill, so that unit went right back later in the day. Meanwhile I noticed that my symptoms with the old unit were now even worse and I could recreate a stall event by moving almost any of the cables, so I decided that enough was enough and it was time to deal with the plug problem because it simply could NOT be PCM related. Upon inspection I noted that the socket connections are NOT simple Molex female as I had been led to believe, but in fact a higher-grade version that uses two gold-plated fingers within the female pin socket shell, and virtually ALL those fingers were in a relaxed, retracted state. I know what these types of connectors look like when new and this was definitely wrong, so the moment I saw that I knew that this was the problem, and it explained all the maddening random behavior and false diagnosis that we all have been going through for so long. This was exactly the type of poor connection that can be affected by the slightest thermal and physical movement, but the question was how to fix it short of getting a brand new harness or three new plugs and splicing them in, or replacing all the pin sockets... a daunting prospect fraught with the threat of misplaced sockets upon reassembly. I decided instead to reset those finger contacts, the method being to hone a dental tool to needle sharpness, put on my most powerful reading glasses and insert the tool between the socket shell and the contact fingers, one by one. If you are a dentist, watchmaker or have worked with electronics all your life (as I have) you will have the requisite hand-eye coordination and dexterity, otherwise I recommend you talk to your dentist or watchmaker. Anyway, I did it (photos attached) and all the problems were instantly cured, including a bonus silencing of the constant PCI bus noise I have been getting in my AM radio for the past five years... and a smoother idle. I was having a similar stalling problem with my '96 RAM 1500, and occasionally rough idle, though much more random and I had not determined whether it was really the PCM or a random crossfire those Magnums have been known to have due to spark wire routing. I did the same restoration on that vehicle and not only did it cure the random miss but I got my torque converter clutch back... no more PO 740. My third vehicle is a '96 GC V8 has the PCI bus noise, so I will be doing that one as well when my daughter brings it home from college. The whole process takes about an hour once you get the hang of it and see how the contact fingers are opposed to each other. Just don't ham-bone it... and make sure you get the right tool for the job. Dentists throw these things out all the time for one reason or another, so it really should not be a problem getting one. Failing that you could use a needle, perhaps a sprung-open safety pin but that would really prove an "all thumbs" operation. The other problem is that with the exception of certain sewing needles most pins have a rather blunt taper, and what you need is a gentle taper that allows you to get behind the finger and then just continue to push the needle in between the shell and the finger to spring it inward. The dental tool I used is gently tapered and due to the "hook" shape allows you to see what you are doing and maintain good control over your movements. Attached are photos, the first shows the tool being inserted behind a finger contact on a completely finished plug... note that you can see the pair of fingers in every socket. The second photo shows a completed plug next to a "before" plug... fingers visible on the gray one, none visible on the white one. After you do this you will note increased resistance when you plug the connector back in, kinda like snapping in as all those fingers part at once, and my advice would be to leave it plugged in there for the NEXT fifteen years. For those of you who have been grappling with these random problems I have no doubt that this will be the last repair procedure you perform, and for those about to tackle these issues it should definitely be the FIRST. A final note - Make sure you disconnect the battery before removing those plugs, and since that will reset the PCM you need to drive for a bit to be sure the problem is resolved... you could still have other issues as the root cause, but this one needs to be ruled out first. Good luck to you all
Solder is a long metal type wire that is used with a soldering iron. The iron has a plastic handle that is round and straight at the base is an electrical cord you plug in. At the top is a long metal shaft it kinda resembles a screw driver. At the tip it comes to a point. When plugged in it gets very hot, you then get the Solder and put it against what you want to fuse together usually wiring of some sort then you put the iron tip to the solder and it melts it on top of the pieces you want to fuse together you lift the iron and remaining Solder carefully away it hardens and viola you have electrical connections safely secured to one another.
Could be the plugs themselves not clicking on to the pcm or the wires in the plugs are loosely connected to the contacts. I'm having this issue exactly for months now both pcm and pcm plugs. I can wiggle the pcm plugs and the car stalls. I fastened the plugs on with a metal bracket. problem went away for weeks, then it came back. I've concluded that the solder is now getting shitty in the pcm. Since the plugs cannot wiggle or come off with the bracket on. Gonna buy a pcm soon but saving to get the jeep rewired and get a modern custom pcm.
I hope this works, I love my Jeep but I am at my fucking witts end with these problems and, I am ready to give up, but I will try this before I do... I will let ya know, p.s. thanks either way..
I had all the connectors soldered and it still stalls out .. Im at a loss guess ill take it out one more time. They took my transporter108 channel name away. so now its Fack Googel because they would not let me type google as my last name.
