NOx failed while getting my integra smog'd

[DB8GSR]

My G2 integra failed the smog test when NOx was measured at over 1100 and the highest passing measures at ~740. This is my commuter with 198k miles on the odo and all I had been doing was just the normal maintenance. This is the first time I've ever had a vehicle failed smog and the tester told me that the integra has dirty valves. He recommended that I should put in some of those injector/valve cleaners and run it for about a week and then come back for a free re-test. Does that sound right to you guys? All the other test like the HC, etc. came out clean, within the below normal range, and the tester said that my cat is fine and nothing to worry.

Here's what i'm going to be replacing and doing in the next few days:
Oil change
Spark plug and wire change
Run Chevron w/ Techron plus one more bottle of that injector cleaner additive
Drink a couple of Heinekens


In that case, is there anything else I should check? For the last year or so, I've been mixing gas with different companies depending on which one sells the cheapest even if it's a few pennies saved. I have 2 weeks before I can go back and re-test, no charge.

[DaveLC2]

My G2 integra failed the smog test when NOx was measured at over 1100 and the highest passing measures at ~740. This is my commuter with 198k miles on the odo and all I had been doing was just the normal maintenance. This is the first time I've ever had a vehicle failed smog and the tester told me that the integra has dirty valves. He recommended that I should put in some of those injector/valve cleaners and run it for about a week and then come back for a free re-test. Does that sound right to you guys? All the other test like the HC, etc. came out clean, within the below normal range, and the tester said that my cat is fine and nothing to worry.

Here's what i'm going to be replacing and doing in the next few days:
Oil change
Spark plug and wire change
Run Chevron w/ Techron plus one more bottle of that injector cleaner additive
Drink a couple of Heinekens


In that case, is there anything else I should check? For the last year or so, I've been mixing gas with different companies depending on which one sells the cheapest even if it's a few pennies saved. I have 2 weeks before I can go back and re-test, no charge.




Yeah those things sound like they would help. If your cat is tired you may need to replace it. Also make sure that your temp is not too high. You may want to run a bottle of that redline water wetter to bring the coolant temp down a bit. Excessive heat is your enemy when smog testing. On the old test it would never caught the nox. That Chevron Techron fuel additive is pretty good stuff. My buddy also uses some air intake cleaner when the car is running too. Just spray in small amounts almost to the point to where the car wants to stall into a vacuum line such as the pcv line. If you don't feel comfortable with doing that the Techron additive will be fine.

Dave

[xevilxviiix]

NOx means that the combustion chamber temps are too high. Im not sure if your car has EGR but if it does, chk that first. If not the cat can be not working effiencently enough. If the HC and CO levels are close to nothing, then it can be running too lean and causing too much heat in the combustion chamber.
basically, you gotta figure out why the combustion chamber temps are so high.

[azn_baller83]

out of topic but what if your HC is too high? this is for a 94 integra GS-R motor...what do you guys think i should check for

[xevilxviiix]

out of topic but what if your HC is too high? this is for a 94 integra GS-R motor...what do you guys think i should check for


HC means raw unburned fuel is coming out. So it means your having imcomplete combustion or running too rich. But usually when you run rich, CO will be pretty high also. chk your plugs and wires and ignition timing. May have a misfire.

[SouthernCrane]

My G2 integra failed the smog test when NOx was measured at over 1100 and the highest passing measures at ~740. This is my commuter with 198k miles on the odo and all I had been doing was just the normal maintenance. This is the first time I've ever had a vehicle failed smog and the tester told me that the integra has dirty valves. He recommended that I should put in some of those injector/valve cleaners and run it for about a week and then come back for a free re-test. Does that sound right to you guys? All the other test like the HC, etc. came out clean, within the below normal range, and the tester said that my cat is fine and nothing to worry.

Here's what i'm going to be replacing and doing in the next few days:
Oil change
Spark plug and wire change
Run Chevron w/ Techron plus one more bottle of that injector cleaner additive
Drink a couple of Heinekens


In that case, is there anything else I should check? For the last year or so, I've been mixing gas with different companies depending on which one sells the cheapest even if it's a few pennies saved. I have 2 weeks before I can go back and re-test, no charge.




i'm having the same problem with my Civic with JDM B16..........hopefully it is going ot get worked out soon. i'll keep you posted ray.

[ek9_evo9]

clean your valves, carbon on your valves maybe a cause of higher than usual nox levels.

also timing....

i had a civic hatch that i fill up with arco religiously....smogged the car and did not fail one bit, car is about 160,000 miles. * its a 2000...i know i know i whore the car to commuting :?

[wzcx]

I've heard it recommended that you fill with 100- bit that's almost as expensive as a new cat!

[azn_baller83]

out of topic but what if your HC is too high? this is for a 94 integra GS-R motor...what do you guys think i should check for


HC means raw unburned fuel is coming out. So it means your having imcomplete combustion or running too rich. But usually when you run rich, CO will be pretty high also. chk your plugs and wires and ignition timing. May have a misfire.


does it matter if you have a after market fuel pump? is that gonna make it run richer??

[DB8GSR]

clean your valves, carbon on your valves maybe a cause of higher than usual nox levels.

also timing....





I've heard it recommended that you fill with 100- bit that's almost as expensive as a new cat!


Those are the things exactly what the tester had told me. He even jokingly told me to run 100oct just for the test and to pass and I was like.. eh?!? But then he said just run 91 and come back. LoL

Does anyone think this may have something to do with the type of gas I put in daily?

[ek9_evo9]

clean your valves, carbon on your valves maybe a cause of higher than usual nox levels.

also timing....






I've heard it recommended that you fill with 100- bit that's almost as expensive as a new cat!


Those are the things exactly what the tester had told me. He even jokingly told me to run 100oct just for the test and to pass and I was like.. eh?!? But then he said just run 91 and come back. LoL

Does anyone think this may have something to do with the type of gas I put in daily?


yes, better quality fuel has better additives which help with breaking up carbon buildup in your valves.

carbon buildup increases the overall temp in your combustion chamber i beleive.....this increase in temp is the reason why nox levels rise. timing is everything too. jdm b16 generally never passes the NOX test because timing is usually 1 degree off.

I wish i can get some tech and confirmation on this but posting with a psp is slowwww.ww

[SouthernCrane]

Ray, i passed the Civic with the JDM B16. I had the valves adjusted, and put in a better cat and it passed without any problems. The cat helped much more than the valve adjustment according to the pre and post tests.

[DB8GSR]

yah.. i think my cat is also pooped. Where did you get your cat at and how much? I was thinking of going to the junkyard and find me a cat.

Also, does yours have an EGR valve?

[SouthernCrane]

yah.. i think my cat is also pooped. Where did you get your cat at and how much? I was thinking of going to the junkyard and find me a cat.

Also, does yours have an EGR valve?


I can't remember the website i got the cat from, but it was a Miller stock replacement, and was about 300 bucks. I had magnaflow cats on there prior to the Miller and those didn't work well (i had two on there)....those were about 100 bucks. Some people i have talked to have said they have passed with cheaper universals that are around 100-200, but i talked to someone that passed with the Miller cat so i bought that one.

No EGR valve.