Passed CA Emissions

[tomtom72]

Originally Posted by tf95ZR1

I know I'm bringing up an old thread, but now this (and more) is an issue for me. I didn't pass CA smog.
Same HC and CO values that passed for the last 5 years now don't pass. My NO was higher than before at 15mph but lower at 25mph(?).
So I'm researching all of this. My understanding is that HC and CO increase with poor/incomplete combustion,
while too hot a combustion increases NO. So there is a "window" of temperature and combustion that is ideal.
Won't wrapping and possibly overheating the CATS increase NO?

What to do, What to do... I know, move to another state.

are the cats the OEM ones? If yes then I would change the O2 sensors as older ones will react a bit slowly over the life span. If the cats are the s/s metal spun substrate then you would do well to have a heat coating on them. s/s cools too quickly, or I should say transfers heat too quickly and the spun metal substrate ones actually do not do as good a job of cleaning up tail pipe emissions.

The trick of Hib's with the EGR is a sweet one! I have a 90 so I would have never thought of that trick! Kudos Hib!!


Tom