olowe29

My TII S5 is failing smog due to high nox. I have the racingbeat turboback exaust
and a 1 year old highflow 3" cat. Right now my acv is rigged to send all of its air from my airpump to the ports. I've also changed my o2 sensor and plugs in the last 2 weeks(same with oil) . So what the hell do I need to do to pass Mf smog?
And please don't say alcohol that will just make it worse (leaner mixture= higher
nox)
Thanks in advance

J's fc

iTrader: (1)

High nox is due to high heat and, high engine psi. if your runnig more than stock boost, chances are that it could be ONE of your suspects. Another thing is that i belive in oakland and in the bay area are what you call a Enhanced area were the smog check is a ASM (Acceleration Simulation Mode). That asm test is to check nox levels. i would check and see if you engine cooling system working correctly. if all else fails get a smog hook up.

Jpk3200

How about the other readings?

Dendrobates

on my old camaro I failed due to high nox (everything else was fine) and it was because I pulled the vac line off the egr valve....just a thought

J's fc

iTrader: (1)

Well that would work to, but you dont want to throw parts at it you want to accurately diagnose the nox problem. Besides what did your hc, co, and nox look like (ppm, parts per million) olowe???

olowe29

I don't think that the car even gets near boost during the 15 and 25mph dyno tests. Unfortunatly the one smog printout I have won't be much help because I was using denatured alcohol. So the HC and CO numbers are really low but my NOX is high, max allowable at 15mph 807ppm I was at 1038ppm. I,ve gone back and done several pretests for free (thank god). The first pretest with no alcohol I was too high on HC and CO but ok on NOX. So after searching the forum I looked and found the acv wasn't routing air to the cat, so I fixed that now all the air is going to the ports. Thats when my NOX went back up. And S5's don't have an egr valve. My god I being long winded

olowe29

olowe is a combo of my first and last name Osiris Lowe, O.K. no stalkers lol

rotorpower27

i have two new cats that i bolt on before i go to smog.
i had issues with smog for a while, i did notice that the cats really only lowered NOX.
if you live close enough you could rent them...
they bolt right in with two flanges.