Currently experiencing slight loss in power, fuel efficiency seems down and
temperature is running substantially higher than what was normal a few
months ago (100-110 C vs.90C). I checked the obvious, no coolant loss,
everything appears ok under hood, no trouble codes, fan comes on at 110C,
etc. Any clues what might be going on. A friend suggested that the catalytic
converter might be causing this problem. If so is there a way to either
confirm or rule it out?