Failed smog, don't know why
#1
Failed smog, don't know why
Hi guys, two years ago my car passed smog
This time it failed horribly,
the only difference Made is that last year during a flood, my exhaust became filled with water. Culd that have damaged it?
I had larger wheels than factory as well. 205/50/15
This time it failed horribly,
the only difference Made is that last year during a flood, my exhaust became filled with water. Culd that have damaged it?
I had larger wheels than factory as well. 205/50/15
#2
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Re: Failed smog, don't know why
Go to an exhaust shop and see if your catalytic converter is still working.
They have a point-and-shoot thermometer that will test the input and output temperatures of the cat to see if it's lighting up properly.
You HC and NO being so high give me the impression that is what the problem is.
Both of those readings will go up with a bad cat.
Also, how did you go about the test?
- lowest octane fuel
- drive car around for 15min or more to get it completely warmed up
- leave car idling while waiting for test
- wait for test no longer than 5 minutes
They have a point-and-shoot thermometer that will test the input and output temperatures of the cat to see if it's lighting up properly.
You HC and NO being so high give me the impression that is what the problem is.
Both of those readings will go up with a bad cat.
Also, how did you go about the test?
- lowest octane fuel
- drive car around for 15min or more to get it completely warmed up
- leave car idling while waiting for test
- wait for test no longer than 5 minutes
#3
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Re: Failed smog, don't know why
Yes, with nox that high and barely failing HC I would be looking at replacing the cat before messing with anything else, it is most likely the problem.
#4
Re: Failed smog, don't know why
Cat huh, I removed it right away and dryed it.
I just found a clogged egr hose too. The one that goes to the back of the intake manifold
I just found a clogged egr hose too. The one that goes to the back of the intake manifold
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Re: Failed smog, don't know why
EGR could be giving you the high NO, but yours is so high that I'm still going to think it's the cat.
If you get a couple free retests then maybe it's worth having another go at it ff your EGR tube was completely clogged. NOx goes up with nonoperative EGR.
CopyPasta-
"To test the EGR valve: Disconnect the vacuum line from the EGR valve to the engine and set it aside. Next, connect a longer hose w/ same inside diameter of the vacuum hose you disconnected to the EGR valve. Do not connect the other end of this test hose to the engine ( to the EGR valve only). Next, start the engine. With engine running, take the other end of the test hose and suck on it (one side of hose connected to the EGR valve and the other end is in you mouth as you are sucking on it). Now get your mind out of the gutter. The engine should run ruff and/or die. IF THE ENGINE DOES NOT RUN RUFF AND/ OR DIE, THE EGR VALVE IS NOT WORKING PROPERLY. This means the EGR needs to be replaced/ rebuilt or there is a blockage."
Also, while sucking on the line, stick the end to your tongue. There is a rubber diaphragm in the EGR that lifts a rod to pass gasses back into the intake. If that diaphragm has a hole in it, then your EGR will not hold vacuum and the hose won't stick to your tongue. Additionally this would be a small vacuum leak. If the hole gets serious enough, then you get an EGR ECU code for lift sensor failure.
The cat didn't need to be dried out as all of the water would have just blown out the exhaust and evaporated. Problem is cats wear out and go bad over time. If you have had engine problems for any period of time they can wear out a cat really quickly. Seeing how your car is a 1991, well... assumption is that the cat is old too.
When is the last time you have done any ignition upkeep - cap, rotor, plugs, wires, timing?
HC is unburnt fuel. If you have a weak ignition system, then HC goes up.
Also, if you have a broken valve or low compression you get lots of fuel going into the exhaust. Your HC number really isn't all that high so my guess is still cat.
If you get a couple free retests then maybe it's worth having another go at it ff your EGR tube was completely clogged. NOx goes up with nonoperative EGR.
CopyPasta-
"To test the EGR valve: Disconnect the vacuum line from the EGR valve to the engine and set it aside. Next, connect a longer hose w/ same inside diameter of the vacuum hose you disconnected to the EGR valve. Do not connect the other end of this test hose to the engine ( to the EGR valve only). Next, start the engine. With engine running, take the other end of the test hose and suck on it (one side of hose connected to the EGR valve and the other end is in you mouth as you are sucking on it). Now get your mind out of the gutter. The engine should run ruff and/or die. IF THE ENGINE DOES NOT RUN RUFF AND/ OR DIE, THE EGR VALVE IS NOT WORKING PROPERLY. This means the EGR needs to be replaced/ rebuilt or there is a blockage."
Also, while sucking on the line, stick the end to your tongue. There is a rubber diaphragm in the EGR that lifts a rod to pass gasses back into the intake. If that diaphragm has a hole in it, then your EGR will not hold vacuum and the hose won't stick to your tongue. Additionally this would be a small vacuum leak. If the hole gets serious enough, then you get an EGR ECU code for lift sensor failure.
The cat didn't need to be dried out as all of the water would have just blown out the exhaust and evaporated. Problem is cats wear out and go bad over time. If you have had engine problems for any period of time they can wear out a cat really quickly. Seeing how your car is a 1991, well... assumption is that the cat is old too.
When is the last time you have done any ignition upkeep - cap, rotor, plugs, wires, timing?
HC is unburnt fuel. If you have a weak ignition system, then HC goes up.
Also, if you have a broken valve or low compression you get lots of fuel going into the exhaust. Your HC number really isn't all that high so my guess is still cat.
#6
Re: Failed smog, don't know why
Oh, the cat is new, and I only use it during smog month
I just got caught in bad luck that one time.
I read that high temperatures can cause high NO numbers, I put a carbon fiber hood on, and I noticed that underhood does feel a bit hotter
I just got caught in bad luck that one time.
I read that high temperatures can cause high NO numbers, I put a carbon fiber hood on, and I noticed that underhood does feel a bit hotter
#7
Re: Failed smog, don't know why
When is the last time you have done any ignition upkeep - cap, rotor, plugs, wires, timing?
HC is unburnt fuel. If you have a weak ignition system, then HC goes up.
Also, if you have a broken valve or low compression you get lots of fuel going into the exhaust. Your HC number really isn't all that high so my guess is still cat.
HC is unburnt fuel. If you have a weak ignition system, then HC goes up.
Also, if you have a broken valve or low compression you get lots of fuel going into the exhaust. Your HC number really isn't all that high so my guess is still cat.
It must have been around 5 k miles ago.
Also the engine is a new one from hmotors.
I had a oil catch can on, inline between the pvc valve
I put a bottle of heet in, because I was told it would help. that plus 87 octane, regular.
New o2 sensor as well
I'll check the plugs and look for exhaust leaks
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#8
MM Gruppe B
Re: Failed smog, don't know why
Use manifold vacuum to test the valve, if it opens, and you have a lift sensor on it, it will not set a code. But if the intake runners have plugs in them remove them, they are the EGR ports to each runner. These will need to be removed to clean the EGR ports so NOx will be reduced. High HCs are most likely from a lean misfire due to the non functional EGR system.
http://home.comcast.net/~em-engineering/T2T013.pdf
That is for 90-93 Accord, but if your manifold is similar with the plugs, it is the same procedure.
For easier port cleaning, use a vacuum and two sizes of flat head screwdriver, a 'trim' size and 'normal' size. Use blades that are square, not ones that taper out. Screw into the carbon first with the larger regular size flat head, when you come to some resistance stop. There is a lip, then use the smaller 'trim' sized flat head to finish drilling through to the runner.
If there is a side port to clear out the main runner you will want to pull that plug and clean it as well.
Use 17199-PT3-AHM to reseal the open ports/plugs if your original plugs are no longer useable. They are only $0.25 each.
http://home.comcast.net/~em-engineering/T2T013.pdf
That is for 90-93 Accord, but if your manifold is similar with the plugs, it is the same procedure.
For easier port cleaning, use a vacuum and two sizes of flat head screwdriver, a 'trim' size and 'normal' size. Use blades that are square, not ones that taper out. Screw into the carbon first with the larger regular size flat head, when you come to some resistance stop. There is a lip, then use the smaller 'trim' sized flat head to finish drilling through to the runner.
If there is a side port to clear out the main runner you will want to pull that plug and clean it as well.
Use 17199-PT3-AHM to reseal the open ports/plugs if your original plugs are no longer useable. They are only $0.25 each.
#9
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Re: Failed smog, don't know why
The more I read this, the less it makes sense.
Can you take a picture of your EGR and the whole overall intake manifold?
Your SMOG print says "N/A" for EGR.
It also says your motor is a 1.6.
Decoding your VIN (found at the top of your SMOG slip) says you have a CRX Si - so it's a D16A6.
JHMED836 it's an HF
JHMED936 is an Si.
I've never heard nor seen an Si D16A6 motor with an EGR.
I've personally owned a DX/LX D15 (california) that had an EGR.
I am also certain the HF has an EGR.
But the D16A6? I really don't think it has one.
MadMike - the D motor manifolds only have a single port on the #4 runner. When you remove the EGR, you can use a solvent (I like B12 chemtool) to get the buildup to loosen. The port exits right above the intake valve in the head. If you really wanted to clear it, you would have to remove the intake manifold to gain proper access to the EGR hole going into the cylinder head. Long pipe cleaners and rifle bore cleaners along with solvent work decently.
Acmoc, rereading and 87 + HEET was probably ok, but it's always better to run without any additives on your first run so you can get a decent baseline for what is going on.
Can you take a picture of your EGR and the whole overall intake manifold?
Your SMOG print says "N/A" for EGR.
It also says your motor is a 1.6.
Decoding your VIN (found at the top of your SMOG slip) says you have a CRX Si - so it's a D16A6.
JHMED836 it's an HF
JHMED936 is an Si.
I've never heard nor seen an Si D16A6 motor with an EGR.
I've personally owned a DX/LX D15 (california) that had an EGR.
I am also certain the HF has an EGR.
But the D16A6? I really don't think it has one.
MadMike - the D motor manifolds only have a single port on the #4 runner. When you remove the EGR, you can use a solvent (I like B12 chemtool) to get the buildup to loosen. The port exits right above the intake valve in the head. If you really wanted to clear it, you would have to remove the intake manifold to gain proper access to the EGR hole going into the cylinder head. Long pipe cleaners and rifle bore cleaners along with solvent work decently.
Acmoc, rereading and 87 + HEET was probably ok, but it's always better to run without any additives on your first run so you can get a decent baseline for what is going on.
#10
Re: Failed smog, don't know why
The more I read this, the less it makes sense.
Can you take a picture of your EGR and the whole overall intake manifold?
Your SMOG print says "N/A" for EGR.
It also says your motor is a 1.6.
Decoding your VIN (found at the top of your SMOG slip) says you have a CRX Si - so it's a D16A6.
JHMED836 it's an HF
JHMED936 is an Si.
I've never heard nor seen an Si D16A6 motor with an EGR.
I've personally owned a DX/LX D15 (california) that had an EGR.
I am also certain the HF has an EGR.
But the D16A6? I really don't think it has one.
MadMike - the D motor manifolds only have a single port on the #4 runner. When you remove the EGR, you can use a solvent (I like B12 chemtool) to get the buildup to loosen. The port exits right above the intake valve in the head. If you really wanted to clear it, you would have to remove the intake manifold to gain proper access to the EGR hole going into the cylinder head. Long pipe cleaners and rifle bore cleaners along with solvent work decently.
Acmoc, rereading and 87 + HEET was probably ok, but it's always better to run without any additives on your first run so you can get a decent baseline for what is going on.
Can you take a picture of your EGR and the whole overall intake manifold?
Your SMOG print says "N/A" for EGR.
It also says your motor is a 1.6.
Decoding your VIN (found at the top of your SMOG slip) says you have a CRX Si - so it's a D16A6.
JHMED836 it's an HF
JHMED936 is an Si.
I've never heard nor seen an Si D16A6 motor with an EGR.
I've personally owned a DX/LX D15 (california) that had an EGR.
I am also certain the HF has an EGR.
But the D16A6? I really don't think it has one.
MadMike - the D motor manifolds only have a single port on the #4 runner. When you remove the EGR, you can use a solvent (I like B12 chemtool) to get the buildup to loosen. The port exits right above the intake valve in the head. If you really wanted to clear it, you would have to remove the intake manifold to gain proper access to the EGR hole going into the cylinder head. Long pipe cleaners and rifle bore cleaners along with solvent work decently.
Acmoc, rereading and 87 + HEET was probably ok, but it's always better to run without any additives on your first run so you can get a decent baseline for what is going on.
I was under the car, and found my cat made a loud ruckus
I took it off, and the inside element is completely gone
So obviously I need a new cat.
I basically did the test with a test pipe.
The honeycomb thing is there, but it's loose and rattling. I will post a video tomorrow.
Also, I will set the timing to 16 degrees since its suppose to be at 18+-2
I'll post a picture of the vacum diagram tomorrow
Thanks guys
#11
Re: Failed smog, don't know why
I keep reading that high NO levels are caused by high engine temps and Not the cat itself
My cat is definetley shot, you guys think it could solve the issue?
This is what I'm going to do
Put stock wheels on
replace spark plugs
fixed vacuum lines
remove oil catch can
replace cat
run some seafoam through the brake booster?
adjust timing to 16 degrees
put stock hood back on
My cat is definetley shot, you guys think it could solve the issue?
This is what I'm going to do
Put stock wheels on
replace spark plugs
fixed vacuum lines
remove oil catch can
replace cat
run some seafoam through the brake booster?
adjust timing to 16 degrees
put stock hood back on
#12
Re: Failed smog, don't know why
Okay, here's my cat, the red is the element sitting sideways in the cat
And the plug that was suck is circled in red
https://www.youtube.com/watch?v=-ltZ...ature=youtu.be
Also, I have a water resistant prefilter on my airfilter. Should I remove it?
And the plug that was suck is circled in red
https://www.youtube.com/watch?v=-ltZ...ature=youtu.be
Also, I have a water resistant prefilter on my airfilter. Should I remove it?
#13
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Re: Failed smog, don't know why
I would set your timing back to 18. That's where it should be.
A lean fuel mixture would cause high NOx so I do not think your pre-filter is hurting. It it were clogged or restricting air, then you would be running rich.
Seafoam would be a good idea - before you replace the cat because all sorts of junk will blow out the exhaust.
You are right about NOx being created by internal engine temps. your hood on the car has little to do with this unless you are seeing your temp gauge on the instrument cluster going up very high. Otherwise, the water cooling system is doing it's job and keeping the internal temps in a good condition.
Here's a list of things that can give you failing NOx SMOG readings;
Misfire condition
Malfunctioning or improperly adjusted EGR valve
Failed oxygen sensor
Leak in exhaust tubing upstream of converter
Excessive carbon deposits in combustion chamber
Improper spark advance
Blocked coolant passage
Overly lean air-fuel mixture
Damaged cold air duct
Failed or malfunctioning catalytic converter
Corroded or damaged engine sensor electrical connections
There are 2 way and 3 way catalytic converters. The three way version will reduce NOx. Your cat is bad if it's rattling around inside. If you get a new cat, be sure to drive for 50 or so miles to get the cat really hot and burn off all the manufacturing debris and to get the cat to light up and work properly inside. Typically a failed cat is a result of something else that is wrong with the car, but you haven't said anything about check engine lights or anything that would suggest that you have really engine problems. Your numbers for the smog test actually look decent to me, but the glaring failures don't look like engine problems to me - I'm no expert by any means... just saying.
The combination of HEET and low octane in your fuel is adding some difficulty to what is wrong. You shouldn't be running any extra additives in your fuel when you test the first time because they do effect the results and maybe not in a good way.
'ISO-HEET' is what you should have ran... not 'HEET'. 'Iso-Heet' is isopropal alcohol and 'heet' is methyl alcohol.
As long as the engine is running well then 2 bottles of ISO-HEET on a near empty tank of fuel and pretty much any car passes... sometimes even without a cat.
A lean fuel mixture would cause high NOx so I do not think your pre-filter is hurting. It it were clogged or restricting air, then you would be running rich.
Seafoam would be a good idea - before you replace the cat because all sorts of junk will blow out the exhaust.
You are right about NOx being created by internal engine temps. your hood on the car has little to do with this unless you are seeing your temp gauge on the instrument cluster going up very high. Otherwise, the water cooling system is doing it's job and keeping the internal temps in a good condition.
Here's a list of things that can give you failing NOx SMOG readings;
Misfire condition
Malfunctioning or improperly adjusted EGR valve
Failed oxygen sensor
Leak in exhaust tubing upstream of converter
Excessive carbon deposits in combustion chamber
Improper spark advance
Blocked coolant passage
Overly lean air-fuel mixture
Damaged cold air duct
Failed or malfunctioning catalytic converter
Corroded or damaged engine sensor electrical connections
There are 2 way and 3 way catalytic converters. The three way version will reduce NOx. Your cat is bad if it's rattling around inside. If you get a new cat, be sure to drive for 50 or so miles to get the cat really hot and burn off all the manufacturing debris and to get the cat to light up and work properly inside. Typically a failed cat is a result of something else that is wrong with the car, but you haven't said anything about check engine lights or anything that would suggest that you have really engine problems. Your numbers for the smog test actually look decent to me, but the glaring failures don't look like engine problems to me - I'm no expert by any means... just saying.
The combination of HEET and low octane in your fuel is adding some difficulty to what is wrong. You shouldn't be running any extra additives in your fuel when you test the first time because they do effect the results and maybe not in a good way.
'ISO-HEET' is what you should have ran... not 'HEET'. 'Iso-Heet' is isopropal alcohol and 'heet' is methyl alcohol.
As long as the engine is running well then 2 bottles of ISO-HEET on a near empty tank of fuel and pretty much any car passes... sometimes even without a cat.
#14
Honda-Tech Member
Re: Failed smog, don't know why
replace spark plugs?
check timing? (dont rely on their check)
warm the car up for 30 minutes before test?
the 15mph NOx is typically high, because the test only starts when it gets below the limit, but the 25mph NOx should not be anywhere near that high.
check timing? (dont rely on their check)
warm the car up for 30 minutes before test?
the 15mph NOx is typically high, because the test only starts when it gets below the limit, but the 25mph NOx should not be anywhere near that high.
#16
Re: Failed smog, don't know why
Yep, changed spark plugs and ran the seafam through the brake booster line. Been driving all day
I should put timimng at 18 not 16?
Should I put two bottles of heet in it? I'm a little confused if that's what you're recommending
I purchased a new cat, just need to weld it
I will remove the pre filter.
I am kind of feeling the cat was the problem
I should put timimng at 18 not 16?
Should I put two bottles of heet in it? I'm a little confused if that's what you're recommending
I purchased a new cat, just need to weld it
I will remove the pre filter.
I am kind of feeling the cat was the problem
#17
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Re: Failed smog, don't know why
I'm recommending you run nothing in your fuel. Get a baseline for what your engine is doing unadulterated.
18 degrees.
LOL @ your cat! that thing is DEAD
18 degrees.
LOL @ your cat! that thing is DEAD
#18
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Re: Failed smog, don't know why
If your honeycomb collapsed like that it's generally a sign of another condition that caused that failure. I've seen plenty of blown out honeycombs and most of them were from overly rich motors or people running 100+ or adding avgas
Your numbers looked the same as mine when I bought a EF with a gutted cat (I didn't know and failed GP). Replacing cat and o2 passed with flying colors.
Your numbers looked the same as mine when I bought a EF with a gutted cat (I didn't know and failed GP). Replacing cat and o2 passed with flying colors.
#19
Re: Failed smog, don't know why
Yes, there was a flood and I had my cat in a toolshed at the time, and my test pipe on the car. The cat became submerged during the flood.
Before that I never had an issue.
I usually run my cat for the month I have to smog it, and my testpipe the rest of the year.
Only after the flood has it collapsed like this
Before that I never had an issue.
I usually run my cat for the month I have to smog it, and my testpipe the rest of the year.
Only after the flood has it collapsed like this
#20
Re: Failed smog, don't know why
I filled up once since the heet, will drive to empty once more and fill up again with 87
Yea, the cat fell apart, I felt like an idiot, I heard that noise but thought it was something else.
I thought it was the spring bolt for the cat, I used washers and extended bolts, the washers almost touch the piping
edit:
Timing at 18
Getting my cat welded, I'll put it on tomorrow
Put the lighter stock wheels on, pump them up really well
Remove the prefilter Just in case
Fill up with regular again (lots of driving today)
And test Friday
Though the friend who is welding it for me mentioned He knows someone who will smog it for 75 if it passes and 120.00 if it needs to be *wink wink type smog
I'll inquire more
Last edited by acmoc; 06-18-2014 at 03:56 PM.
#21
Re: Failed smog, don't know why
failed smog again guys =[
numbers were worse than before
Could it be the ebay header?
I see the actual real dc sports header has the o2 sensor routed towards the end, whereas this one has it on only one? That would make it run lean, make the NO numbers high right
numbers were worse than before
Could it be the ebay header?
I see the actual real dc sports header has the o2 sensor routed towards the end, whereas this one has it on only one? That would make it run lean, make the NO numbers high right
#22
Re: Failed smog, don't know why
I hope I can get some kind of extension.
The smog guy gave me some valuable info.
I feel like an idiot if it turns out to be true.
My car used to give a cel for 02 sensor.
I figured it was the failing fuel pressure regultor. So I put an adjustable one on it and turned up the fuel pressure.
He told me it's odd for the o2 sensor to be on one primary, it will make it run lean and the cobustion chamber will be hot=high NO numbers
So I check online for an actual dc sports header. and the 02 bung is at the end where all four primaries collect
I have a spare 02 sensor. I'm going to put the stock regulator back on, and extend the wire so it can reach the end. y header doesn't have a bung there, but my test pipe does, so if I get no CEL, I think I' found my problem, I'll order a dc sports header
The smog guy gave me some valuable info.
I feel like an idiot if it turns out to be true.
My car used to give a cel for 02 sensor.
I figured it was the failing fuel pressure regultor. So I put an adjustable one on it and turned up the fuel pressure.
He told me it's odd for the o2 sensor to be on one primary, it will make it run lean and the cobustion chamber will be hot=high NO numbers
So I check online for an actual dc sports header. and the 02 bung is at the end where all four primaries collect
I have a spare 02 sensor. I'm going to put the stock regulator back on, and extend the wire so it can reach the end. y header doesn't have a bung there, but my test pipe does, so if I get no CEL, I think I' found my problem, I'll order a dc sports header
#23
Honda-Tech Member
Re: Failed smog, don't know why
Yes, DC header has it back at the end of the collector near the cat.
OEM o2 sensor location only has it on one runner close to the head.
ive passed with both.
wait what? why did you up the fuel pressure? you dont think this is a problem???
OEM o2 sensor location only has it on one runner close to the head.
ive passed with both.
My car used to give a cel for 02 sensor.
I figured it was the failing fuel pressure regultor. So I put an adjustable one on it and turned up the fuel pressure.
I figured it was the failing fuel pressure regultor. So I put an adjustable one on it and turned up the fuel pressure.
#24
Re: Failed smog, don't know why
Yea, I thought it was the FPR, it seems I just masked it by upping the pressure.
Now I bet there's carbon buildup from the forceful rich run
I put the o2 sensor in the back and the oem fpr back on, my guess is if my cel doesn't come back, I found my problem