Scott at AAPerformance Muffler tested the cat a couple days ago and said the temps (180 degrees IIRC) shows its running rich and he suggested a clogged EGR pipe. Can bad 02 sensors cause it to run rich? I have put 101,000 miles on the truck myself so they should be on their way out. I don't have cash for parts that may good for a bit longer. The obvious thing is to find a VOM and test it, thanks Robbie.
1988 FJ62 - gone
2005 4Runner Limited V8