Grand cherokee keeps dieing randomly
#46
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Heres the thing guys, from my experience and others I have talked to. There is an order to troubleshooting this..
First- Once you isolate which connector is causing the problem, you need to pull back any tape and/or tubing. Check the wires a good 12" back. Once you have done this and there is no visible damage that you can see, then look around the rest of your harness for indications of previous owners hacking or Jerry rigging crap up.
Second- if no damage can be found then try to isolate an individual wire. Tug, pull, move around ONE wire at a time. Most of the time it's a ground wire that is faulty but not always. If you can isolate a single wire as being the cause, find out which wire it is and check the other end for damage or being loose. Also you can pull the connector off and look inside at the pin and see if it has been moved, pushed back up inside or dirty,etc... If none of this seems to work, move to #3
Third- if you can or even if you can't isolate to a particular wire and no signs of damage are visible, then with motor running move the actual connector around. With mine I had to grab to wires going in at lift upward, forcing the connector IN and to angle downward. If I did this the engine ran fine but as soon as I let go it died. Problem was PCM. this happens over time the solder joints on the PCM can become weak and break. When you put it to a certain position it makes connection, but without that force it doesn't. At this point you need to replace PCM.
Check my post before on my opinion of companies VS dealer...
My cost from dealer was $577 plus one hour of labor to flash and install. That is pretty standard, I called 6 dealers. It is under a 1year warranty. And 99% of the time if it is going to break it will either happen within that time or it will last years to come.
First- Once you isolate which connector is causing the problem, you need to pull back any tape and/or tubing. Check the wires a good 12" back. Once you have done this and there is no visible damage that you can see, then look around the rest of your harness for indications of previous owners hacking or Jerry rigging crap up.
Second- if no damage can be found then try to isolate an individual wire. Tug, pull, move around ONE wire at a time. Most of the time it's a ground wire that is faulty but not always. If you can isolate a single wire as being the cause, find out which wire it is and check the other end for damage or being loose. Also you can pull the connector off and look inside at the pin and see if it has been moved, pushed back up inside or dirty,etc... If none of this seems to work, move to #3
Third- if you can or even if you can't isolate to a particular wire and no signs of damage are visible, then with motor running move the actual connector around. With mine I had to grab to wires going in at lift upward, forcing the connector IN and to angle downward. If I did this the engine ran fine but as soon as I let go it died. Problem was PCM. this happens over time the solder joints on the PCM can become weak and break. When you put it to a certain position it makes connection, but without that force it doesn't. At this point you need to replace PCM.
Check my post before on my opinion of companies VS dealer...
My cost from dealer was $577 plus one hour of labor to flash and install. That is pretty standard, I called 6 dealers. It is under a 1year warranty. And 99% of the time if it is going to break it will either happen within that time or it will last years to come.
#47
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Roll4life.. Idk if the engine dying cause the piston to collapse or not. It was at 190k. Maybe just age and wear. But I would address the connection/electrical before going anywhere far. Last thing you want is to break down away from home
#48
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Year: 1990
Model: Cherokee
Engine: 4.0 I6
Got the new connectors on and all tightened up and now she runs like a freaking champ
No problems do far but I'll give it a week before I call it done
No problems do far but I'll give it a week before I call it done
#49
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Year: 1997
Model: Grand Cherokee
Engine: 4.0
Heres the thing guys, from my experience and others I have talked to. There is an order to troubleshooting this..
First- Once you isolate which connector is causing the problem, you need to pull back any tape and/or tubing. Check the wires a good 12" back. Once you have done this and there is no visible damage that you can see, then look around the rest of your harness for indications of previous owners hacking or Jerry rigging crap up.
Second- if no damage can be found then try to isolate an individual wire. Tug, pull, move around ONE wire at a time. Most of the time it's a ground wire that is faulty but not always. If you can isolate a single wire as being the cause, find out which wire it is and check the other end for damage or being loose. Also you can pull the connector off and look inside at the pin and see if it has been moved, pushed back up inside or dirty,etc... If none of this seems to work, move to #3
Third- if you can or even if you can't isolate to a particular wire and no signs of damage are visible, then with motor running move the actual connector around. With mine I had to grab to wires going in at lift upward, forcing the connector IN and to angle downward. If I did this the engine ran fine but as soon as I let go it died. Problem was PCM. this happens over time the solder joints on the PCM can become weak and break. When you put it to a certain position it makes connection, but without that force it doesn't. At this point you need to replace PCM.
Check my post before on my opinion of companies VS dealer...
My cost from dealer was $577 plus one hour of labor to flash and install. That is pretty standard, I called 6 dealers. It is under a 1year warranty. And 99% of the time if it is going to break it will either happen within that time or it will last years to come.
First- Once you isolate which connector is causing the problem, you need to pull back any tape and/or tubing. Check the wires a good 12" back. Once you have done this and there is no visible damage that you can see, then look around the rest of your harness for indications of previous owners hacking or Jerry rigging crap up.
Second- if no damage can be found then try to isolate an individual wire. Tug, pull, move around ONE wire at a time. Most of the time it's a ground wire that is faulty but not always. If you can isolate a single wire as being the cause, find out which wire it is and check the other end for damage or being loose. Also you can pull the connector off and look inside at the pin and see if it has been moved, pushed back up inside or dirty,etc... If none of this seems to work, move to #3
Third- if you can or even if you can't isolate to a particular wire and no signs of damage are visible, then with motor running move the actual connector around. With mine I had to grab to wires going in at lift upward, forcing the connector IN and to angle downward. If I did this the engine ran fine but as soon as I let go it died. Problem was PCM. this happens over time the solder joints on the PCM can become weak and break. When you put it to a certain position it makes connection, but without that force it doesn't. At this point you need to replace PCM.
Check my post before on my opinion of companies VS dealer...
My cost from dealer was $577 plus one hour of labor to flash and install. That is pretty standard, I called 6 dealers. It is under a 1year warranty. And 99% of the time if it is going to break it will either happen within that time or it will last years to come.
#50
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Year: 1997
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what did you do, rob a harness with PCM connectors off a another Jeep and splice it into yours? was it your connectors or the PCM?
#51
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^ got a junk yard connector and wires
Spliced onto the old wires
PCM appears to be fine I'm pretty sure this problem is solved for now
Spliced onto the old wires
PCM appears to be fine I'm pretty sure this problem is solved for now
#52
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Glad to hear that 1990... How much did you pay for the connectors? I got the one I needed for $3 plus $4 for a warranty( take it back and get another one if needed)... Did you solder wires or use butt connectors to put on the new connector? I wouldn't recommend using connectors cause water can get it. Solder it and then wrap it with heat-shrink.... Glad I could help
DeepSouth. The reason I didn't add that step is because resoldering a board is a bit more complex than most peoples capabilities. I won't even break into a vehicle ECM/PCM because I don't have the schematics for it. Without a comprehensive electronics background and understanding, not to mention the actual schematics, you will do no more than render whatever it is that you are working on completely useless... Lol
And by the way I have been building/repairing electronics for 8 years including 4 years working on microwave radio terminals for the Marine Corps...
DeepSouth. The reason I didn't add that step is because resoldering a board is a bit more complex than most peoples capabilities. I won't even break into a vehicle ECM/PCM because I don't have the schematics for it. Without a comprehensive electronics background and understanding, not to mention the actual schematics, you will do no more than render whatever it is that you are working on completely useless... Lol
And by the way I have been building/repairing electronics for 8 years including 4 years working on microwave radio terminals for the Marine Corps...
#53
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It was 1$ I think so I didn't get a warranty or anything
But I got it with a bunch of other junk for my other truck
I used the but connectors with heat shrink and tape I think it should be fine
- I'm in el paso so I don't think I'll have to worry about water much
But I got it with a bunch of other junk for my other truck
I used the but connectors with heat shrink and tape I think it should be fine
- I'm in el paso so I don't think I'll have to worry about water much
#54
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Year: 1997
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Glad to hear that 1990... How much did you pay for the connectors? I got the one I needed for $3 plus $4 for a warranty( take it back and get another one if needed)... Did you solder wires or use butt connectors to put on the new connector? I wouldn't recommend using connectors cause water can get it. Solder it and then wrap it with heat-shrink.... Glad I could help
DeepSouth. The reason I didn't add that step is because resoldering a board is a bit more complex than most peoples capabilities. I won't even break into a vehicle ECM/PCM because I don't have the schematics for it. Without a comprehensive electronics background and understanding, not to mention the actual schematics, you will do no more than render whatever it is that you are working on completely useless... Lol
And by the way I have been building/repairing electronics for 8 years including 4 years working on microwave radio terminals for the Marine Corps...
DeepSouth. The reason I didn't add that step is because resoldering a board is a bit more complex than most peoples capabilities. I won't even break into a vehicle ECM/PCM because I don't have the schematics for it. Without a comprehensive electronics background and understanding, not to mention the actual schematics, you will do no more than render whatever it is that you are working on completely useless... Lol
And by the way I have been building/repairing electronics for 8 years including 4 years working on microwave radio terminals for the Marine Corps...
The Honda TRX300 CDI box is a prime example of solder joints failing in a solid state. We use hose clamps and wrist pins to apply pressure to the internal joints to make contact. Worked for a good long time.
#55
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Nice, yea unless TX get another monster hurricane, but it'd be the least of your worries then.. Lol.
Yea I'd just assume not even mention it. I know how I am and if someone says it, I try anyway...lol then sit there with all the pieces going" why did I do this? " lol no insult taken..
Well now I have an issue that has happened twice. Hit about 2-3 gear and the RPMs hit around 1700 and it tries to cut out for a second then goes away. Happened twice, but not in the last few days, so we shall see with time
Yea I'd just assume not even mention it. I know how I am and if someone says it, I try anyway...lol then sit there with all the pieces going" why did I do this? " lol no insult taken..
Well now I have an issue that has happened twice. Hit about 2-3 gear and the RPMs hit around 1700 and it tries to cut out for a second then goes away. Happened twice, but not in the last few days, so we shall see with time
#56
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Well I now have a misfire on cylinder 1, cylinder 2 spark plug looks like it's got about 20k miles on it( only 900 since rebuild).. Uphill the problem is worse. Leaning towards fuel, maybe pump or injectors, heck I don't know... Taking it to napa today
#57
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Year: 1990
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Well of its just the one cylinder I don't think it will be a pump or something like that
I would check out the injector first then the spark plug to
Mine had a # 4 miss fire but the injector wires were broke and wile driving it shook like a mother and smell like it burning
Your probly runs bad up hill cuz of the miss
Kinda obvious stuff but
Hope this helps some
I would check out the injector first then the spark plug to
Mine had a # 4 miss fire but the injector wires were broke and wile driving it shook like a mother and smell like it burning
Your probly runs bad up hill cuz of the miss
Kinda obvious stuff but
Hope this helps some
#58
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Year: 1997
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Well of its just the one cylinder I don't think it will be a pump or something like that
I would check out the injector first then the spark plug to
Mine had a # 4 miss fire but the injector wires were broke and wile driving it shook like a mother and smell like it burning
Your probly runs bad up hill cuz of the miss
Kinda obvious stuff but
Hope this helps some
I would check out the injector first then the spark plug to
Mine had a # 4 miss fire but the injector wires were broke and wile driving it shook like a mother and smell like it burning
Your probly runs bad up hill cuz of the miss
Kinda obvious stuff but
Hope this helps some
I wounder if a new injector harness may be in order for us????
#59
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Year: 1990
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Theres a good way to test the injector wires by hooking up a light to the harness where the injector would be and run the motor and if the light flashes normally then it's probly not the injector harness