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-   -   Failed smog again! (https://honda-tech.com/forums/tech-misc-15/failed-smog-again-777028/)

mark72 Feb 23, 2004 10:04 AM

Failed smog again!
 
I had my car smogged last friday and failed due to
high nox. The day before i had a new carsound cat installed,
changed my spark plugs, and changed my oil.
I have a 95' integra ls w/119000 and AEM intake and
DC headers. My readings were MAX:711
My measure: 891
I passed the other catagories. Would having a bad o2 sensor
have a huge effect for high nox readings?

mark72 Feb 23, 2004 10:56 AM

Re: Failed smog again! (mark72)
 
ttt

mark72 Feb 23, 2004 01:49 PM

Re: Failed smog again! (mark72)
 
bump. need some advice

MightyMouseTech Feb 23, 2004 07:06 PM

Re: Failed smog again! (mark72)
 
Are you sure the cat you installed is a three way cat? If it isn't, that will send your NOx readings way up. Also, a lazy O2 sensor will increase NOx readings as well.

Billy Blaze Feb 23, 2004 07:25 PM

Re: Failed smog again! (mark72)
 
You said it a carsound cat? If you are driving a 95 Integra that should be OBDII. Car sound does not make a OBDII cert cat converter. I know its not CARB leagal. Chances are its not a 3 way cat.

mark72 Feb 23, 2004 07:46 PM

Re: Failed smog again! (SoCalAutotech)
 
mine is obd1. i dont know if the cat is a three way cat.

Cory man Feb 23, 2004 08:42 PM

Re: Failed smog again! (mark72)
 
High Nox is from high combustion temps. Make sure you arent running extremely lean as this would cause high NoX. Good luck!!

boostn420 Feb 23, 2004 09:30 PM

Re: Failed smog again! (Cory man)
 
High Nox can also be caused by exhaust leaks especially closer to the engine than the muffler. Itll also help clean it a little so if you find one and fix it expect the other values to rise a little.

mark72 Feb 23, 2004 09:42 PM

Re: Failed smog again! (boostn420)
 
im not really that technical about cars. how would
i know if im running lean?

boostn420 Feb 23, 2004 09:47 PM

Re: Failed smog again! (mark72)
 
You dont have the mods needed to run lean. So dont worry about it. The spark plugs would be very white still.

turtle-eg Feb 23, 2004 10:20 PM

Re: Failed smog again! (mark72)
 
Did you get your engine nice and hot(warm) before you went to the smog test? If not, this could be your reason... Drive around town in first and second gear pulling to 5-6k before shifting to warm up everything. Also, we fixed an '91 Integra two weeks ago failing NOX at 15mph because of a bad PCV, you might wanna try that also.

Btw, the integra we worked on also had a new aftermarket cat. welded on by the owner right before he came in.

mark72 Feb 23, 2004 10:39 PM

Re: Failed smog again! (turtle-eg)
 
yeah i drove around for a while before i had it smogged.
is a pcv valve expensive?


Modified by mark72 at 4:25 PM 2/24/2004

Oh Crap Feb 23, 2004 11:40 PM

I'm not too familiar with that brand cat. but if it's a high flow.. that's probably your problem.

mark72 Feb 24, 2004 05:26 PM

Re: (Oh Crap)
 
thanks for the help peoples.
i replaced my pcv valve and next to be relaced
is my o2 sensor.

carcala Feb 24, 2004 06:06 PM

Re: (mark72)
 
it could be ur cat. I failed smog with a carsound cat which was practically new and used a brand new oem cat and passed. i would also check spark plug gap and plugs that came with the car. alsotry putting back ur stock intake and header. that helped me with my smog. if that doesnt do it try a new o2 sensor cause it could be going bad.

Kidnkorner Feb 24, 2004 06:26 PM

run 87 octane, and pour a bottle of rubbing alcohol into your tank

buy a bottle of sea foam, and follow the intsructions

MightyMouseTech Feb 25, 2004 04:26 AM

Re: Failed smog again! (mark72)
 
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mark72 &raquo;</TD></TR><TR><TD CLASS="quote">yeah i drove around for a while before i had it smogged.
is a pcv valve expensive?


Modified by mark72 at 4:25 PM 2/24/2004</TD></TR></TABLE>

I wouldn't worry about the PCV, I have only ever seen 2 valves go bad in all my years of working as a Honda Tech. And both of those situations were due to HUGE amounts of blowby coupled with lack of regular oil changes.

mark72 Feb 25, 2004 05:30 PM

Re: (Huggy Bear)
 
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Huggy Bear &raquo;</TD></TR><TR><TD CLASS="quote">run 87 octane, and pour a bottle of rubbing alcohol into your tank

buy a bottle of sea foam, and follow the intsructions</TD></TR></TABLE>

wtf is sea foam and who carry's it?

JohnnyEG Feb 25, 2004 06:15 PM

Re: Failed smog again! (mark72)
 
Change your DC headers back to your stock LS headers. DC headers are Carb E.O. but try it out with your stock headers on. Check your timing also, I believe your stock ignition timing is supose to be 16 degrees. You might want to retard your timing a little to lower the NOX. You are allowed 16 degrees plus or minus 2 degrees. So you can be at 14 degrees and still be within specs to pass inspection and maybe even your smog check. And make sure your whole exhaust system is sealed up pretty good without any air leaks. You are not to far off, as I've seen numbers near 3000.

Kidnkorner Feb 26, 2004 02:36 PM

Re: (mark72)
 
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mark72 &raquo;</TD></TR><TR><TD CLASS="quote">

wtf is sea foam and who carry's it?</TD></TR></TABLE>

napa, and it removes carbon deposits in the cumbustion chambers intake and exhaust runners

photec2 Feb 26, 2004 09:06 PM

Re: (Huggy Bear)
 
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Huggy Bear &raquo;</TD></TR><TR><TD CLASS="quote">run 87 octane, and pour a bottle of rubbing alcohol into your tank

buy a bottle of sea foam, and follow the intsructions</TD></TR></TABLE>

i would read this before using seafoam https://honda-tech.com/zerothread?id=780762

dip-set Feb 27, 2004 05:45 AM

Re: Failed smog again! (SoCalAutotech)
 
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SoCalAutotech &raquo;</TD></TR><TR><TD CLASS="quote">You said it a carsound cat? If you are driving a 95 Integra that should be OBDII. Car sound does not make a OBDII cert cat converter. I know its not CARB leagal. Chances are its not a 3 way cat.
</TD></TR></TABLE>

your off to the left buddy...
96+ obd2
carsound does make obd2 cats

mark72 Mar 22, 2004 09:38 AM

Re: Failed smog again! (b18b-se)
 
does timing play a huge factor towards
high nox?

hair_rice Mar 22, 2004 09:51 AM

Re: Failed smog again! (Billy Blaze)
 
95's are OBD1

mark72 Mar 23, 2004 10:30 PM

Re: Failed smog again! (hair_rice)
 
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hair_rice &raquo;</TD></TR><TR><TD CLASS="quote">95's are OBD1</TD></TR></TABLE>
i know that. i just want to know if
timing is an important issue when smogging a car?


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