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Old 05-17-2020, 09:51 PM   #14 (permalink)
rmay635703
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Quote:
Originally Posted by California98Civic View Post
That would be a problem. But Hondas such as the Gen1 Insight, Civic VX, and CIVIC HX have not had that problem & they run as lean as 22:1, according to Wikipedia. 18:1 is not nearly as lean and it would produce a modest improvement in emissions and in fuel economy. I don't understand why it was ever phased out, if it was phased out, for light load cruising and moderately low engine speeds. I gotta think it is still programmed into Honda iVEC systems but not promoted.
Older cars (pre 2000) had 2 way CATS or modified 3 way
which aren’t affected by that issue, they also more importantly didn’t need to meet the more stringent NOx limits of later years so some NOx could pass a full trap without issue.


The Insight and newer had a Nox trap and would cycle lean to rich to make sure the cat stayed lit and the NOx levels didn’t increase after the NOx trap filled.
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