Failed Smog NOx

[n2motorsports]

I just failed my smog test today.
HC & CO passed with flying colors but I failed in the NOx department.  the car is a 91 318is, completely stock besides COP conversion.

Max was 815 @ 15 MPH but I got a 944 (not the porsche).

My cat is new ~ less then 6 mos.
New spark plugs
filter looks okay

only thing I haven't changed and probable causes:
small crack in the intake boot from the filter to the TB (would this effect idle?)
o2 sensor history unknown
and the dumbest, i didn't warm up the car properly before the test

would the COP conversion effect timing?

TIA

[tjts1]

Go back to the smog tech, raise hell and have them retest it for free because THEY failed to warm up your car first! I had a smog tech test my car almost complete cold and it passed NoX 814 or out of max 815. It is their responsibility to make sure the engine is at operating temp.

[quinn11m20]

Hey are you in California? There might be a product out there called "Guarenteed to pass" by CRC. Go to Auto Zone or to a Pep Boys. I have used it before and passed. Then when all is said and done. Move out to Florida. We don't have vehicle inspections and smog tests.

[n2motorsports]

Hey are you in California? There might be a product out there called "Guarenteed to pass" by CRC. Go to Auto Zone or to a Pep Boys. I have used it before and passed. Then when all is said and done. Move out to Florida. We don't have vehicle inspections and smog tests.

yes, arnold's got us by the balls here in CA.  they even have random smog checkpoints cropping up everywhere.

[quinn11m20]

ha ha. I used to live in San Luis Obispo and Santa Barbara. I know about the clean air act out there. Seriously though you should try that product. I have used it and passed. But this was back in 97. Good Luck.