Electrical problem, no spark.

[Griffin6]

Okay, I’m new to the site and hope I am asking this question in the right place and forum. I have a 1983 CJ7 that came from the Toledo factory installed with the AMC 4-cylinder engine. I know, those didn't show up until 1984, but what can I say? Even I was surprised when I picked up the Jeep in fall of 83 after returning from a tour of duty in Germany.

I've kept the Jeep virtually stock except for adding a Weber 2barrel Carb about 4 years ago. Its been running great. Good pickup, especially for a 4 cyl. A few weeks back, it was hard to start, finally caught although running rough. I turned it off and it remains dead. I replaced the ignition module as that was usually the culprit in the past. No go. I traced the system and all wiring is good. I did a nutter bypass a half dozen years ago and it's been running great. I have a lot of new spare parts so I started by replacing the coil, coil connector, solenoid (even though it turns over great) plugs, cap, rotor, and the pick up coil in the distributor. Bottom line, no spark at the plugs. I used one of your threatpds and checked the power to the ignition module and that is fine. I probed the coil connector with a test light (bulb, not LED) and the red wire is bright when in run and start. The green wire is very dim in Run, and I get no light on the green wire in start. Knowing the ignition modules are notorious for being bad out of the box, I installed a second new spare. Still no spark. I'm stumped. Suggestions?

 

[Belizean]

I had that engine in my 84 for over 35 years and I loved that simple engine with a Weber and the last 8 - 10 years with a MSD coil and CD box that reawakened the engine. I got close to 1/4 million miles before replacing the 4 with a 6. What kind of mileage does your engine have ?

 

[Griffin6]

I had that engine in my 84 for over 35 years, and I loved that simple engine with a Weber and the last 8 - 10 years with a MSD coil and CD box that reawakened the engine. I got close to 1/4 million miles before replacing the 4 with a 6. What kind of mileage does your engine have ?

I have just over 200K. I did have the head rebuilt a few years ago and other than some routine maintenance, and tender loving care, it's been a reliable. I'm the first to admit, the AMC 4 banger has been a good little engine. Now that I have some time on my hands, I am considering upgrading to a 6cyl engine, like you.

 

[Belizean]

Has the timing chain and sprockets been replaced ? Right at about 140,000 miles mine started running like at idle and stalling when pulling up for a light or stop sign. That caused the timing to go a little crazy.

 

[NP435]

I have just over 200K. I did have the head rebuilt a few years ago and other than some routine maintenance, and tender loving care, it's been a reliable. I'm the first to admit, the AMC 4 banger has been a good little engine. Now that I have some time on my hands, I am considering upgrading to a 6cyl engine, like you.

I had a similar problem with my AMC 258 i6 / 4.2l 6 banger, solution was a hot wire to a switch on the dash then to my HEI distributor, if you dont have HEI this may not cure you.

 

[Griffin6]

Has the timing chain and sprockets been replaced ? Right at about 140,000 miles mine started running like at idle and stalling when pulling up for a light or stop sign. That caused the timing to go a little crazy.

Yes, I changed the sprocket and timing chain when I had the head rebuilt. Using a timing light is near impossible to get right. I get a much smoother idle and more power doing so by ear.

 

[Griffin6]

I had a similar problem with my AMC 258 i6 / 4.2l 6 banger, solution was a hot wire to a switch on the dash then to my HEI distributor, if you dont have HEI this may not cure you.

If you can believe it, I still have the stock distributor although I have rebuilt it a few times.