High Hc's after Y
#1
High Hc's after Y
Ive looked at other threads but none except one come close to my specification. My cars since 06 since I had it has passed with flying colors both times, getting HC reading of like 7ppm. So I change my Y pipe with the warpspeed. I did replace a o2 sensor, it got rid of my code for the o2 sensor but I dont even kno if that o2 sensor is working or not, its an o2 sensor going into the y pipe. So i test my car now here at school and the HC now is 241ppm! I went from perfect passing to this 241. Is it simply the y pipe, or like ive read do i need to adjust the bpt valve to adjust to this new pressure loss so it has to activate? if so anyone know how to check the bpt valve or adjust it to make it work correctly? My numbers were:
At Idle Only:
HC-241
CO-.45
CO2-11.3
o2- 2.0
Nox-82
Btw im in Cali. Smog will be harder to pass here.
At Idle Only:
HC-241
CO-.45
CO2-11.3
o2- 2.0
Nox-82
Btw im in Cali. Smog will be harder to pass here.
#3
the elimination of such pre cats would increase the Hc's by this much? Doesnt the main cat only really concentrate on reducing Nox? Im still thinkn its the bpt valve, anyone know how to make sure that thing can work with the new y pipe?
#5
lol put your stock y back on.. an aftermarket y will make you fail in cali. in cali your max needs all the cats it can have to pass.
use an obd2 scanner or volt meter to test the o2 sensor.
use an obd2 scanner or volt meter to test the o2 sensor.
#6
Yep yep! Do you still have the inline cat? If not ... add one! Also, make sure you got a good seal at the Y and manifold, it this is leaking and not pushing all the gasses out the end, it will throw off the readings too.
#7
The stock y makes a huge difference. Over the years i've run across four maximas that haven't passed smog with aftermarket ypipes. I find hard to believe that all of them had an i'll adjusted bpt valve.
As soon as a stock y, and stock cat were in place they passed with flying colors. Remember high HC's are due to unburnt fuel, a cat burns that excess fuel off. If cat is not there, then... you get the picture.
Last edited by 99greddymax; 10-29-2010 at 12:41 PM.
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