Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice?
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From: San Diego, CA, San Diego
Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice?
My CRX just failed CA smog. 
I rebuilt the motor about 100 miles ago with new rings and valve stem seals.
The CO2 is at 14.8%, O2 at 0. HC are low, 15ppm, with max of 134. CO is low too, .02% with max of .82%. Only the NO failed at 1052 with max of 847.
At higher speed the NO dropped down to 437 which was a pass.
The car was burning a lot of oil before the rebuild, due to a burnt valve and shot rings. Can I hope that this might burn out with more miles and I can then pass it? Or have I ruined my cat with so much oil burning?
Any other advice?
EDIT : 3/10/6- Passed.
A new O2 sensor, new spark plugs, and a tank of 87. I pulled the timing back 2 degrees or so, and also tightned a few bolts before the cat that may have been loose.
The Nox reading dropped down to half of MAX, while the CO and HC went up a bit. Thank for all the advice guys....
Modified by shbrown at 2:31 PM 3/10/2006
I rebuilt the motor about 100 miles ago with new rings and valve stem seals. The CO2 is at 14.8%, O2 at 0. HC are low, 15ppm, with max of 134. CO is low too, .02% with max of .82%. Only the NO failed at 1052 with max of 847.
At higher speed the NO dropped down to 437 which was a pass.
The car was burning a lot of oil before the rebuild, due to a burnt valve and shot rings. Can I hope that this might burn out with more miles and I can then pass it? Or have I ruined my cat with so much oil burning?
Any other advice?
EDIT : 3/10/6- Passed.
A new O2 sensor, new spark plugs, and a tank of 87. I pulled the timing back 2 degrees or so, and also tightned a few bolts before the cat that may have been loose.
The Nox reading dropped down to half of MAX, while the CO and HC went up a bit. Thank for all the advice guys....
Modified by shbrown at 2:31 PM 3/10/2006
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Re: Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice? (shbrown)
My A6 took a long time to burn all the **** out of the cat, both coolant and oil. You might as well replace the cat, I would say gut it but you're in Cali.
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From: Pittsburgh, PA
Re: Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice? (downest)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by downest »</TD></TR><TR><TD CLASS="quote">You might as well replace the cat, I would say gut it but you're in Cali.</TD></TR></TABLE>
Even if he wasn't in Cali, gutting the cat still wouldn't help him pass emissions.
Even if he wasn't in Cali, gutting the cat still wouldn't help him pass emissions.
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From: San Diego, CA, San Diego
From what I have read, as my HC and CO numbers were low, that indicates that the cat is OK, right?
It was a bitch to fit the downpipe into the inlet of the cat, maybe it is leaking there. I read somewhere that a leak pre-cat could cause high NO. Is this true for my A6?
It was a bitch to fit the downpipe into the inlet of the cat, maybe it is leaking there. I read somewhere that a leak pre-cat could cause high NO. Is this true for my A6?
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From: San Diego, CA, San Diego
All #'s
Hello and thanks for any responses. Here are all of the Emmission Test
Result numbers from my failing test report:
= = = = = = = = = = = = = = =
Line 1:
Test=15mph
RPM=1972
%CO2 meas=14.8
%02 meas=0.0
HC (PPM) MAX=134, AVE=31, MEAS=15
CO (%) MAX=0.82, AVE=0.10, MEAS=0.02
NO (PPM) MAX=847, AVE=237, MEAS=1052
FAIL
= = = = = = = = = = = = = = =
Line 2:
RPM=2087
%CO2 meas=14.8
%02 meas=0.1
HC (PPM) MAX=108, AVE=20, MEAS=15
CO (%) MAX=0.71, AVE=0.09, MEAS=0.06
NO (PPM) MAX=786, AVE=199, MEAS=437
PASS
= = = = = = = = = = = = = = =
Result numbers from my failing test report:
= = = = = = = = = = = = = = =
Line 1:
Test=15mph
RPM=1972
%CO2 meas=14.8
%02 meas=0.0
HC (PPM) MAX=134, AVE=31, MEAS=15
CO (%) MAX=0.82, AVE=0.10, MEAS=0.02
NO (PPM) MAX=847, AVE=237, MEAS=1052
FAIL
= = = = = = = = = = = = = = =
Line 2:
RPM=2087
%CO2 meas=14.8
%02 meas=0.1
HC (PPM) MAX=108, AVE=20, MEAS=15
CO (%) MAX=0.71, AVE=0.09, MEAS=0.06
NO (PPM) MAX=786, AVE=199, MEAS=437
PASS
= = = = = = = = = = = = = = =
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Re: All #'s (shbrown)
Here is what you do.
Nox is caused by high combustion temps. Did your smogman use a fan?
He could of ran the car hot. This would do it. tell him to run the test over with the fan on high.
Timing. set your timing to 16 btdc. Your emissions sticker should specify 18 btdc + or - 2 deg. use it, go to 16.
When you reset the timing reset the computer. and drive it for twenty miles then let it cool to below 160 deg. and run it for another 20
Also run 87 octane gas.
You have to only drop 200ppm's these should do it for you.
Oh yea, burning oil will not effect your readings unless it is plugging the cat
As for exhaust leaks It would give more O2 to the cat so a small exhaust leak should not matter. Your cat is dropping the O2 to 0.0 which is a good thing.
SH
Nox is caused by high combustion temps. Did your smogman use a fan?
He could of ran the car hot. This would do it. tell him to run the test over with the fan on high.
Timing. set your timing to 16 btdc. Your emissions sticker should specify 18 btdc + or - 2 deg. use it, go to 16.
When you reset the timing reset the computer. and drive it for twenty miles then let it cool to below 160 deg. and run it for another 20
Also run 87 octane gas.
You have to only drop 200ppm's these should do it for you.
Oh yea, burning oil will not effect your readings unless it is plugging the cat
As for exhaust leaks It would give more O2 to the cat so a small exhaust leak should not matter. Your cat is dropping the O2 to 0.0 which is a good thing.
SH
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From: San Diego, CA, San Diego
He used a fan, but the hood was closed. Timing was already set to 16btdc. I had 91 octane and drove it up a big hill to warm up, than back to the smog place on the freeway.
To me, it looks like the cat is working OK, from the O2 #s and the HC and CO.
Could the car just be running lean? When I had my mini-me head (before the rebuild) on it was detonating a lot. It has the same O2 sensor, so my current theory is buring a lot of oil (bad rings before and during mini-me) fouled the O2 sensor, casuing a lean mixture(now and then). Is this possible?
To me, it looks like the cat is working OK, from the O2 #s and the HC and CO.
Could the car just be running lean? When I had my mini-me head (before the rebuild) on it was detonating a lot. It has the same O2 sensor, so my current theory is buring a lot of oil (bad rings before and during mini-me) fouled the O2 sensor, casuing a lean mixture(now and then). Is this possible?
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From: San Diego, CA, San Diego
And a 'tired' O2 sensor would/could cause a lean condition? I am going to try testing the output voltage tonight according to my Helm's. What should I look for that might indicate it is making my car run lean?
If the O2 sensor is reading rich when it is fact running stoich, would that then cause the computer to cut the fuel down and run lean?
If the O2 sensor is reading rich when it is fact running stoich, would that then cause the computer to cut the fuel down and run lean?
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Re: (shbrown)
nox is cat related replace the cart and you will pass i have dealt with the same problem time and time again i can pass on co and hc with a gutted cat so yeah...lol
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Re: Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice? (shbrown)
If your car was burning ALOT of oil, it is possible that you killed the oxygen sensor and/or catalytic converter. You might want to look into replacing both of these. The oxygen sensor is cheaper. So you might try replacing this first and see what happens. But if this doesn't help, then the cat is likely gone. As for the hydrocarbons being low, it is possible that the oxidation catalyst is still viable, but the reduction catalyst could be dead. In this case, the cat needs to be replaced.
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From: San Diego, CA, San Diego
Yeah, it was burning quite a bit for a while. A quart every 500 miles or so. I didn't realize the cats have two stages... Learn something new every day. I think I'll do the O2 1st, and try again to smog it.
Any word on what to look for when testing the O2 sensor?
Any word on what to look for when testing the O2 sensor?
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Re: (shbrown)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by shbrown »</TD></TR><TR><TD CLASS="quote">Any word on what to look for when testing the O2 sensor?</TD></TR></TABLE>
Yeah it will throw a code if it isnt it isnt bad the O2 sensor will let you know when its bad. im telling you from dealing with plenty of cat related emmissions its your cat replace it and you will see **** even if you go to a bone yard and steal a used one it would probably work also you can get a cat for like 80 or so bucks.
Yeah it will throw a code if it isnt it isnt bad the O2 sensor will let you know when its bad. im telling you from dealing with plenty of cat related emmissions its your cat replace it and you will see **** even if you go to a bone yard and steal a used one it would probably work also you can get a cat for like 80 or so bucks.
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Re: (Vinceg99)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Vinceg99 »</TD></TR><TR><TD CLASS="quote">
Yeah it will throw a code if it isnt it isnt bad the O2 sensor will let you know when its bad. im telling you from dealing with plenty of cat related emmissions its your cat replace it and you will see **** even if you go to a bone yard and steal a used one it would probably work also you can get a cat for like 80 or so bucks.</TD></TR></TABLE>
An oxygen sensor can be bad enough to fail emissions testing, but not bad enough to throw a check engine light. You might as well just replace it. After all, those single wire sensors can be had for next to nothing.
Yeah it will throw a code if it isnt it isnt bad the O2 sensor will let you know when its bad. im telling you from dealing with plenty of cat related emmissions its your cat replace it and you will see **** even if you go to a bone yard and steal a used one it would probably work also you can get a cat for like 80 or so bucks.</TD></TR></TABLE>
An oxygen sensor can be bad enough to fail emissions testing, but not bad enough to throw a check engine light. You might as well just replace it. After all, those single wire sensors can be had for next to nothing.
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Re: (d16efhatch)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by d16efhatch »</TD></TR><TR><TD CLASS="quote">im so glad i live in michigan 
</TD></TR></TABLE>
Here in California we drive around, windows down, all day and all night. In California we don't have to deal with snow, black ice, salted roads, gravel and winter tires. I would gladly deal with emissions testing, than all the above. I'm so glad I live in California!
</TD></TR></TABLE>Here in California we drive around, windows down, all day and all night. In California we don't have to deal with snow, black ice, salted roads, gravel and winter tires. I would gladly deal with emissions testing, than all the above. I'm so glad I live in California!
Re: (hazw8st)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hazw8st »</TD></TR><TR><TD CLASS="quote">Here in California we drive around, windows down, all day and all night. In California we don't have to deal with snow, black ice, salted roads, gravel and winter tires. I would gladly deal with emissions testing, than all the above. I'm so glad I live in California!</TD></TR></TABLE>
LOL
Oh man, I was a GROSS POLLUTER when I went for my 1st emission test, but I past the NO (PPM). Maybe because you where using the 91 and the car was having a hard time burning the gas. Use all the 91 first to clean the system than fill up with the 89 next time to test it.
The emission is free after you fail right?
LOL
Oh man, I was a GROSS POLLUTER when I went for my 1st emission test, but I past the NO (PPM). Maybe because you where using the 91 and the car was having a hard time burning the gas. Use all the 91 first to clean the system than fill up with the 89 next time to test it.
The emission is free after you fail right?
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Re: (FOMULA91)
I tried to smog my car when I got it, it was obvious that the headgasket was blown. The tech said that the NO's would be through the roof. So it could be that your HG is leaking. Normally NO is from unusually high combustion temperature otherwise (too much timing maybe). They are formed at temperatures above ~2000 degress from what I understand.
That or maybe its all of that NAWWZZZ
That or maybe its all of that NAWWZZZ
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From: Montoursville, Pa, USA
Re: Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice? (shbrown)
I used to live in vegas every gas station had 110 octain, when ever I was due for smog I would run 1 tank thru, and refill with 110 before I go for smog. I don't know if that is an option for you or not.
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Re: Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice? (ef hatchie)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ef hatchie »</TD></TR><TR><TD CLASS="quote"> I used to live in vegas every gas station had 110 octain, when ever I was due for smog I would run 1 tank thru, and refill with 110 before I go for smog. I don't know if that is an option for you or not. </TD></TR></TABLE>
Yes, there are a couple of stations that have 110 octane.
Yes, there are a couple of stations that have 110 octane.
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From: San Diego, CA, San Diego
Well, I doubt it is my head gasket... I did a pretty good job putting it all back together again. I hope I did it right!
And about octane?? I seem to be getting conflicting reports, some people say higher is better, and some say lower is better. Anyone have a good explaination for either side?
And about octane?? I seem to be getting conflicting reports, some people say higher is better, and some say lower is better. Anyone have a good explaination for either side?
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Re: (shbrown)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by shbrown »</TD></TR><TR><TD CLASS="quote">
And about octane?? I seem to be getting conflicting reports, some people say higher is better, and some say lower is better. Anyone have a good explaination for either side?</TD></TR></TABLE>
Depends on the tuning. You can make it pass on 87 or 110, it solely reflects on the tuning.
And about octane?? I seem to be getting conflicting reports, some people say higher is better, and some say lower is better. Anyone have a good explaination for either side?</TD></TR></TABLE>
Depends on the tuning. You can make it pass on 87 or 110, it solely reflects on the tuning.
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Re: (hazw8st)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hazw8st »</TD></TR><TR><TD CLASS="quote">
Here in California we drive around, windows down, all day and all night. In California we don't have to deal with snow, black ice, salted roads, gravel and winter tires. I would gladly deal with emissions testing, than all the above. I'm so glad I live in California!</TD></TR></TABLE>
Here in GA we have none of those things or emissions tests. Most of the time I can get away with having the windows down, though I like my car to be cold inside regardless of ambient air temp. Hell, we don't even have car inspections. I'm glad I don't live in either one of those places
Here in California we drive around, windows down, all day and all night. In California we don't have to deal with snow, black ice, salted roads, gravel and winter tires. I would gladly deal with emissions testing, than all the above. I'm so glad I live in California!</TD></TR></TABLE>
Here in GA we have none of those things or emissions tests. Most of the time I can get away with having the windows down, though I like my car to be cold inside regardless of ambient air temp. Hell, we don't even have car inspections. I'm glad I don't live in either one of those places
Re: (es330td)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by es330td »</TD></TR><TR><TD CLASS="quote">Here in GA we have none of those things or emissions tests. Most of the time I can get away with having the windows down, though I like my car to be cold inside regardless of ambient air temp. Hell, we don't even have car inspections. I'm glad I don't live in either one of those places</TD></TR></TABLE>
But you guys have Hurricane.
BTW, I used 89 octane to pass my smog, and also used G2P emission but I’m not to sure if that helped.
But you guys have Hurricane.
BTW, I used 89 octane to pass my smog, and also used G2P emission but I’m not to sure if that helped.
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Re: Rebuilt D16A6 failed CA smog, 15MPH NO only. Advice? (shbrown)
You barely didnt pass, so no you dont need to do any drastic repairs.
Pulling back timing will drop nox a whole bunch. If you are at stock timing, pull 2 degrees and you will still be in spec. So if you are at 16 btdc, move it to 14btdc. IMO, this is all you will need to change to pass.
You can also fill up with higher octane, as it also reduces nox. If you already are using the highest octane avail then just pull timing a couple degrees. Do not use octane boosters, I read somewhere that they somehow dont help with nox.
Take a look at this chart. It has been very useful for me:
http://www.firstfives.org/faq/smog/smog_faq.html
Pulling back timing will drop nox a whole bunch. If you are at stock timing, pull 2 degrees and you will still be in spec. So if you are at 16 btdc, move it to 14btdc. IMO, this is all you will need to change to pass.
You can also fill up with higher octane, as it also reduces nox. If you already are using the highest octane avail then just pull timing a couple degrees. Do not use octane boosters, I read somewhere that they somehow dont help with nox.
Take a look at this chart. It has been very useful for me:
http://www.firstfives.org/faq/smog/smog_faq.html