Originally Posted by jeep95xj
Do you have a check engine light on? Most likely if your cat is bad the CEL will come on. If you dont then just get under your jeep and hit the cat with a closed fist. Sometimes when it's broken up inside it will rattle all around when you hit it.
No check engine light. Could I possibly have bad O2 sensors even though they are only a few months old?
Originally Posted by Double E
Give it a kick or with a rubber mallet to see what may rattle around in there. You may have more than one issue however and I'm still suspicious of the cooling system.
"Im not losing an excessive amount of coolant but I did notice this black gunky stuff underneath my radiator cap and there was like little sparkle things floating on top of my coolant. I opened up my coolant reservoir and it looks a little brown around the edges."
Pull that reservoir and flush it out. Replace, Fill it, draw a line on it & monitor it.
Im gonna have to wait to at least tomorrow to anything since its been pouring outside all day. Ill update once its nice enough to do some work.