Dauntless Misfiring Random

I need some advice. My dauntless has been running great for many many years. Suddenly it started backfiring gunshots out of the exhaust. To the point where its undriveable. I somehow barely limp it home. Then it drives great for another 3 weeks. Then its undriveable again for a night.

I put in a hei distributor. New plugs. New wires. Its really hard to trouble shoot because most if the time it runs good.

I was thinking vaccum leak in the intake or carb, but i sprayed them down with carb cleaner while it was running rough and it didnt change the idle.

It seems to be getting worse and more common as time goes on. I pulled all the plugs and they are coco brown like they should be. I do burn quite a bit of oil tho. Always have. But thats getting worse as the years go by too

Any advice?

 

Pull the distributor cap and look for carbon tracking. Are the times it runs poorly associated with damp or rainy days?
It sounds like an ignition issue, and you might be getting cross-firing. Also check the plug wires. Start up the Jeep after dark, and observe the wires with no lights shining in the engine bay. If you have a light show, you've found your problem.
-Donny

 

You might also check your timing chain, as it wears it might of jumped a tooth.