idle miss

[callerys]

I've got a 84 CJ with the original AMC 258 i6 / 4.2l at 94k miles. Runs good but slight miss at idle. It's got Howell FI and Teamrush.

Last thing to replace I think would be the stock ignition box. When these go bad is it total failure or does it degrade?

Any other ideas?

 

[Jimbos76cj]

I think when they go out ts normally a total failure. You upgraded to the bigger cap? how are your wires? I was going to do the stealth HEI upgrade but found a really good deal on a MSD 6AL so I ended up getting that. Double check every thing for shorts, cracked wires, burnt spots. Maybe a coil also.

 

[Torxhead]

The results may vary when an ignition control module goes out, ignition missing is one of them. If your check engine light is not on, it could be a bad module. A bad pick up coil in the distributor or the ignition coil are other possibilities also, those two can be easily checked. So you have different possibilites of what it could be. It is always good to carry or a spare module anyway.

 

[callerys]

Ya I upgraded to the bigger cap along with new wires and rotor. Coil is probably 5-6 years old.

This issue was present before the Howell and before the cap/rotor etc.

Any suggestions on where to get a box?

 

[Jimbos76cj]

Napa.. any of the usual parts stores. I would look into the Stealth HEI. Uses a HEI module inplace of the motorcraft box. It costs about $20 to do and is wired using the same wiring as the ignition box. If you have the stealtch HEI set up and it ever burns out you can replace it with a GM HEI module or a standard ford/Jeep module.

Supposedly the HEI module is a step up from the Jeep box.

 

[Torxhead]

Your issue could be a bad pick up coil in the distributor, a bad module does make the engine perform worse over a short period of time, a givaway is that it is bad if is warm to the touch when it is running. The orange and violet wires coming out of the distributor are for the pick up coil and should check at 600-800 ohms with a meter. The best module you can buy is made by the Echlin brand sold at N.A.P.A., mine was $80. at the time or you can get one from Autozone for $25.