1991 240sx failed smog, high HC & NO.

[cd1921]

ok i need some help guys, i fail smog yest. Im located in So Cal. i have been reading that it might be my EGR valve. im gonna check it out later today or tomorrow when the rain stops, and im going to do the SEAFOAM thing.

wha do u guys think. here are the results that i got from my smog test.

15MPH RESULTS

%CO 12.9 %O2 2.5

HC(PPM)MAX 118 MEAS 166 FAILED

CO%MAX .75 MEAS .63

NO(PPM)MAX 799 MEAS 1223 FAILED

25MPH RESULTS

%CO 12.9%O2 2.4

HC(PPM)MAX 93MEAS 123 FAILED

CO%MAX .63MEAS .48

NO(PPM)MAX 738MEAS 594

any help is welcome guys, or advise. please let me know. or u can email me [email protected]

Modified by cd1921 at 6:25 PM 3/3/2006
Modified by cd1921 at 6:26 PM 3/3/2006

[180fan]

NOx at low speed, your EGR's vacuum isn't that strong. I'd start replacing the vac hoses that go to the EGR, especially the one that runs from the BPT to the EGR.

How are the spark plugs by the way? Can you tell us what the coating on the tips looks like? Is it black and sooty, wet, dry, possibly white in color? Details!

[hazw8st]

http://www.firstfives.org/faq/smog/smog_faq.html