Need help failed smog... - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

S-Nation S13 · 03-06-2008, 11:48 AM

ya i have the same problem..ill cruise on the freeway and the cel will come on then after awhile the dam thing will turn off again..the next day it will do it again..i hooked up a nissan consult obd1 ecu scanner egr and o2 came up ...im planning to change out my entire egr system as well as my o2 sensor cause i have high co at low speed and high nox at high speed there are the only two i failed at smog tech told me that the numbers switch at thats what caused me to fail..along with my timing being at 10 tdc rather than 20 tdc...i know fsm allows +/- 2 degrees tdc so imma put it as low as possible to optimize combustion btw my cat is new the white fabric mesh inside the cat..remarkably is hella white any way i can lower co and nox w/o changing entire egr????

03-06-2008, 11:48 AM	#23
S-Nation S13 Post Whore! Join Date: Jan 2008 Location: LAND of the LOST Posts: 4,083 Trader Rating: (92) Feedback Score: 92 reviews	ya i have the same problem..ill cruise on the freeway and the cel will come on then after awhile the dam thing will turn off again..the next day it will do it again..i hooked up a nissan consult obd1 ecu scanner egr and o2 came up ...im planning to change out my entire egr system as well as my o2 sensor cause i have high co at low speed and high nox at high speed there are the only two i failed at smog tech told me that the numbers switch at thats what caused me to fail..along with my timing being at 10 tdc rather than 20 tdc...i know fsm allows +/- 2 degrees tdc so imma put it as low as possible to optimize combustion btw my cat is new the white fabric mesh inside the cat..remarkably is hella white any way i can lower co and nox w/o changing entire egr????