View Full Version : Curious...NOx levels???

08-03-2002, 02:04 PM
Had my bird go through emissions yesterday and now wonder what yalls NOx levels are like. Maybe its time for me to get new exhaust.

low speed(15mph)@1112 RPM

high speed(25mph)@1294 RPM

08-03-2002, 08:22 PM
PSI level in your cylinders is to high. Cats are partly cloged. Change the cats you should be OK.

Kurt Sr

08-04-2002, 02:02 PM
I had same NOx problem last friday. Mine was running about 760 at 15mph and 730 at 25 mph. I have a 93 with 119K miles and "supposedly" good cats but I wonder..........


08-07-2002, 12:55 AM
My car passed emissions and appears to be stock
and here are the results, if you want a idea of what might
be baseline reading for a SC.


25mph test -- only in rush hour would this be "high speed"
RPM 2002

HC 35ppm
CO .08%
CO2 13.6%
O2 .01%
NOX 206ppm

15mph test - indeed a "low speed"
RPM 1298

HC 85ppm
CO .16%
CO2 13.4%
O2 .2%
NOX 173ppm

10-19-2002, 06:22 PM
I just had my car inspected today and I failed the NOx test and the CO test.

Limit 0.59
Reading: 0.60 (figures....)

Limit: 786
Read: 2917 (AHH!!! a lil on the high side...hehe)

My thoughts are replacing the cats with aftermarket ones as well as the SCP downpipes. I'm in the air though as to whether or not I want to do anything past that....is there a resenator I can buy that is better than the stock one?

Thanks for any help!

10-19-2002, 06:28 PM
if its just NOx its probably your EGR valve if you have one. Or your car is running too hot