P0432 pops up every so often, then just goes away on its own...it reads to be cat. inefficiency bank 2, but I just smogged the jeep, and it passed with flying colors, of course, I had the light reset before I took it for smog...my question is, is that if it was really a cat, wouldn't it fail, regardless wether the light was on or off?

I'm thinking an o2 sensor is the main culprit...

 

Shotgun a new sensor in there. Here's a pic that shows the NTK O2S' by part number and position - that you should be using.

 

Nice..thank you! I'll give it a try