I have a single cat aftermarket exhaust on my 1995 80, which I think may be causing my p420 (cat inefficiency) error.
There are no exhaust leaks.
(the most common cause of p420)
The vehicle also passes emissions.
(10ppm hc, with 111ppm being the fail point).
So here's my theory: Maybe I screwed up distance between the pre-cat O2, the cats, and the Post-cat O2
This would certainly annoy the computer from a cycle timing perspective.
So, could someone with a stock 95-97 80 please measure:
1) From the pre-cat O2 to the first cat
2) The length of both factory cats
3) From the end of the cats to the post-cat O2 sensor
I suspect of I correct these distances in my design, my computer will be happy again...
There are no exhaust leaks.
(the most common cause of p420)
The vehicle also passes emissions.
(10ppm hc, with 111ppm being the fail point).
So here's my theory: Maybe I screwed up distance between the pre-cat O2, the cats, and the Post-cat O2
This would certainly annoy the computer from a cycle timing perspective.
So, could someone with a stock 95-97 80 please measure:
1) From the pre-cat O2 to the first cat
2) The length of both factory cats
3) From the end of the cats to the post-cat O2 sensor
I suspect of I correct these distances in my design, my computer will be happy again...
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