85 CJ7 258 idles then dies w/ video posted

[Torxhead]

Electrical items to consider would be the coil,icm, and distributor pick up coil. The coils can be tested but the icm can be iffy. The distributor pick up coil should be getting 600-800 ohms between the orange and purple wires at the distributor plug, but my experience with those is just a crappy running engine. The coil could be a culprit, they should get around 1.35 ohms between the two outer posts. The icm is tricky so a spare should always be close by.

 

[mtnwhlr]

Does it still have the plastic clip for the wires on the coil? They are and would recommend getting rid of it. It worked for me.

 

[moranda]

Yes I do have the plastic clip on the coil. I checked the coil and it read 2 ohms at the post and then I checked the plug on the distributor and it read 630 ohms. I looked down at the electrical contact on the coil and it did not look in good shape. Is this what they are suppose to look like? I should probably go ahead and replace this right? It is the original one so it has served its time.

 

[rufus1138]

personally yes, i would ditch that.

 

[Hedgehog]

Or clean it up.

 

[mtnwhlr]

This is what I did and have never had any more problems.

 

[moranda]

mtnwhlr that's what I am going to do as well and while i'm getting my hands dirty I might as well do a team rush upgrade. Also do those coils have a negative and positive posts? Asking mostly out of curiosity I figure i will find out as soon as I pick one up.

 

[mtnwhlr]

mtnwhlr that's what I am going to do as well and while i'm getting my hands dirty I might as well do a team rush upgrade. Also do those coils have a negative and positive posts? Asking mostly out of curiosity I figure i will find out as soon as I pick one up.

I replaced mine when I did the Team Rush upgrade and it helped alot and yes it has a - @ +. I got all my parts from Napa but the coil and it came from Autozone.

 

[moranda]

Ok so I got a new ignition coil and did a team rush upgrade and she fired right up...... and then cut out again. I think I have a much more serious problem than I realized. I think that I have a bad head gasket. Today while it was running the smoke coming out of the tail pipe was white (which suggests antifreeze?) and when I would stab the throttle it turned blueish which would mean burning oil. Does this sound like correct logic and would this be causing the problems i have been having?

 

[Torxhead]

Ouch! I think you should start with a spark plug inspection and compression test. Edit: Noticing that you still have that stalling out issue and if you want to question the ignition control module you could put your hand on it an feel whether it is hot to the touch, after a stall out. You could even take it out and get it checked at a local auto parts, You could also buy another one, since having a spare with a CJ is a good thing.

 

[mtnwhlr]

Ouch! I think you should start with a spark plug inspection and compression test.

I was sure hopeing that would fix it for you.

 

[moranda]

I was hoping that as well but the things I changed around needed to happen so I view them as improvements. I changed my spark plugs just the other day because they where carbon fouled so the new ones have not been in long that long. I did pull them out when doing the team rush upgrade. They were darker in color but nothing really alarming. Also you can see a picture of the spark plugs i took out in post #13. Those spark plugs had been in maybe 5k miles.

 

[mtnwhlr]

A compression test will tell you the condition of your motor.

 

[moranda]

Just did a compression check and it looked good the readings were:
cyl 1: 155 psi, cyl 2: 162 psi, cyl 3: 160 psi, cyl 4: 165 psi, cyl 5&6: 160 psi

Also my ICM is cool to the touch and is not oozing anything out of it. I am going to figure out what is wrong with this thing.

 

[Torxhead]

Since you have that new coil, hopefully one with bolt on terminals. you might want to recheck that with an ohm meter. If it checks good fine, if not there must be a short circut or something damaging the coil. It could still be the icm, maybe take that in and get it checked. There could also still be a carb issue that went unchecked, like if you pull out a spark plug and if it is black, there could be a fuel mixture problem stalling out the engine plus blowing dark smoke out the exaust. With the Team Rush done the spark plug gap can go to around .040-.045.

 

[moranda]

I tested the ignition coil and it was reading .7 ohms which is what msd rates it at. Pulled the ICM had it checked it and it was bad so i replaced it. Jeep still behaves the same way except now it does not sputter and choke out it just stops. Should I turn my attention back to the carb? Maybe idle mixtures or something?

 

[Torxhead]

I am quite surprised at the ohm specs for the msd coil! Another possibility would be a frayed or broken wire somewhere, and the later CJs have a lot of wires. This can be tested by jiggling wires around as the engine is idling. Especially at the two fusible links coming off the battery side of the starter relay, these can become weak with age, and they should not be able to stretch.

 

[Neuner]

Something is happening at the 30sec to 1min mark. You need air, fuel and spark to get fire. You have spark and did good with getting the copper set. Your electrical could probably be improved upon but I don't think that is the overall problem. Next is fuel and air. You are idling which creates the greatest vacuum and stress on the vacuum lines but it's still starting and idling so I don't think that is the problem.

When you click the key just before starting, if you're fuel pump is electric, it kicks on and builds up pressure in the line. It could be that you're only running for 30 secs because the gas pressure and supply is adequate only for that duration of time. It drops and thus the engine stops. This would lend me to believe that your fuel pump is not putting out enough pressure/failing or there is some restriction before or after the fuel pump. The carbon build up on your spark plugs are probably due to the restrictive nature of the Platinums but even then it seems excessive so I think you are also running too rich and need to adjust your carb mix.

 

[moranda]

The fuel pump I have is the O.E. one that came with the motor and it is a mechanical pump. I forgot to mention this but I took the inlet line off the fuel pump and ran a piece of hose down into a 5 gallon can of gas just to make sure that there was no blockages or something in the fuel tank creating a clog. The motor still died out and I checked the pump and showed the results in post #15. What doesn't make logical sense to me and my logic has been flawed before is that the motor would run and idle normally then die out. So the fuel mixture is normal and then about a minute into idling becomes rich? Is this possible? Another observation is it seems that after it sits overnight or for several minutes not trying to crank it over, then when I do finally crank it over it seems more eager to start up and idle. When I crank it over after immediately dying it sometimes wont start back up and will need to be cranked for several seconds.

 

[moranda]

One more thing I forgot to mention. Ever since installing the new ICM the motor will sometimes start to die and then rev back up and start to die and then rev back up. It will do this back and forth for about a minute. Another thought is could I have a bad ECU? I've always heard that these ECU's are . Should I look into getting this checked next? Could a good ICM and a bad ECU cause this sort of trouble?