Quote
Originally posted by teamzr1:
....Converters may also fail if they get too hot. This can be caused by unburned fuel in the exhaust. Contributing factors include a rich fuel mixture, ignition misfire (a fouled spark plug or bad plug wire) or a burned exhaust valve that leaks compression. Fuel in the exhaust has the same effect as dumping gasoline on a bed of glowing embers. Things get real hot real fast. If the converter’s temperature climbs high enough, it can melt the ceramic substrate that supports the catalyst causing a partial or complete blockage inside. This increases backpressure, preventing the engine from exhaling and robbing it of power. Fuel consumption may shoot up and the engine may feel sluggish at higher speeds. Or, if the converter is completely plugged, the engine may stall after starting and not restart.
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Interesting, since COT is not reading a sensor, but appears to be calculated somehow, it adds richness.

That would decrease exhaust temperature, but having fuel dumped in to the cats is not good either.

Doesn't add up.