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Old 11-26-2008, 10:44 PM   #39 (permalink)
roflwaffle
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Camryaro - '92 Toyota Camry LE V6
90 day: 31.12 mpg (US)

Red - '00 Honda Insight

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Quote:
Originally Posted by Christ View Post
You assume, by this statement, that all cars are OBD-2... not all cars have a post cat O2 sensor, and even a large number of those that do, only use it to see whether the catalyst is actually doing something, not to adjust the fuel/air mixture.

IIRC, it wasn't until the advent of OBD-2b that the post-cat O2 sensor's signal was used to help adjust AFR in comparison to the signal from the pre-cat sensor.
Even then it still wouldn't get hot enough over warm up. We need obscenely rich, like unburnt gas all the time, to heat up a cat to the point where it's damaged. Not just a little richer during warm-up. At least AFAIK.
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