The only part of the California smog test it failed was the 15mph NOx.
My reading was 901ppm with 835ppm max allowed. The 25mph NOx was half the max allowed.
The HC was 80ppm with 130ppm max and the CO was .06% with .80% max allowed.
What are some of the things that might be causing a high NOx with everything else OK?
I don't know much about this stuff.
Thanks,
Bill Mudd