CJ7 intermittent running issue

#1
My jeep has had this issue pretty much since I have owned it and now is getting a little worse and I am finally getting around to working on it. Its a 258 with the nutter bypass, upgraded ignintion coil, cap, button, wires, etc. Sometimes when I am driving it will just shut off. I can push the clutch in, hit the switch, and it will start right back up while rolling. lately half the time it does it multiple times in a row and will back fire a few times. also sometimes it will go down the road and just fall on its face. motor stays running but every time I hit the gas it bogs. then like a flip of a switch 20-30 sec. later it will be fine. issues seem to be more prevalent in the mornings when the moisture is up in the air, foggy, etc. The foggy morning last week when leaving work it did not want to start, ran like crap from the get go, backfired, etc. I drove home from work (only 6 miles) it ran bad the whole way. went back out at 3.5 hrs later (when the sun was out good) to pick up my daughter from pre school and it ran fine all the way to Lexington and back. Has anyone dealt with this??
 
#2
I've dealt with a bad ignition module but it was pretty consistent that once the vehicle got warm it would start acting up. I've had a bad coil before but it just died and never came back.

Are you seeing any variation in the voltage when it happens like the power is dropping off? I did have an issue with my Jeep in Harlan where my ignition switch was being touchy and was cutting ignition power as soon as I stopped cranking.
 
#4
Seeing very little movement from the volt gauge. But I will definitely be paying more attention to that now.

Nope doesn't have a TPS sensor....yet. Been thinking about a 4.0 HO swap for a long time. maybe one day.

Anyway the brother in law had a old spare ICM. I just removed the bypass and hooked his up for now. it started up and ran. now just to sneak out for a test drive when time permits (maybe the storms in the area can produce the same temp/air moisture as the morning rides). If that goes well a good early morning drive and we shall see. Really hope this helps this thing is driving me crazy shutting down and re starting 6 times and 6 miles on one drive and smooth sailing the next drive. thanks for the help.
 
#5
Depending on year of cj7 they used a ford based duraspark ignition that is not great. Gets job done, but it can be replaced with a six series ignition box from msd or mallory both good units. Very simple install and a great update. Easier starts in all climates and smoother acceleration. My .02.
 
#6
That, or just drop in an HEI dist. I did that when I installed the Howell EFI setup on mine. Power, Ground, and tach wire to the Howell unit and it runs great.Just power and ground on a carb'd motor.
 
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