The pain in the ass YJ (I love it though) strikes again.
So I have a newly rebuilt MC2100 on my 4.2L. I've advanced the timing to about 8 degrees BTDC and done the Nutter Bypass. Also, I've got a brand new Flowmaster Catalytic Converter and muffler.
Basically, after tuning my Jeep for a bit, and driving around my neighborhood (about 30 minutes of running), I happened to notice a bright orange glow under my Jeep. Turns out my Cat was bright orange.
After some research, I've found that it could be running too rich, to lean, or just a bad cat.
Has anyone had this before and know what they did to fix it?