90q fails emissions

[PN <pajono@ctconnect.com>]

I took the new 90q through CT emissions today and failed miserably for high 
Nitrous Oxides (3726 ppm, max allowed is 1121 ppm).

Possible causes listed for the NO failure are bad O2 sensor, bad cat and 
high compression caused by excessive carbon deposits. Do these sound 
reasonable? It's possible I have a clogged cat, and that might explain why 
the car also doesn't like to rev. Is it possible to see the honeycomb in 
the 90q cats, or does the tubing into and out of the cat bend?

Thanks for any input, and any BTDT experiences,
Paul
90 90q 20v
86 944