Was their a loss of power? Did you replace cat's? Common sense would dictate that temp should reduce down the exaust trail, not go up. Engine headers can get close to 1200 degrees Fahrenheit, as the spent exaust makes it's way to the tailpipe it's dropped way down, put your hand there at tailpipe gases, feels no more than 150 degrees. I think the reason the cat temp goes up instead of down, is the conversion process of breaking all the bad stuff down, like nitric oxide, carbon monoxide, and other nasty things, and make them breathable. Anybody here old enough to remember the 70's remember that bad smog in Los Angeles, and other metro areas. In theory it sounds backwards like you said. I did read an answer from advanced Auto parts that confirmed your theory. But all the rest said higher not lower exiting towards rear. This weekend I'm going to check my Eddie Bauer, and see what temps I get. My Suv runs fine, with no misfires or fuel dumping, so I'm assuming mine are ok. As long as we don't get too much rain this weekend, I'll post my findings.
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