Emmisions Failed

[dill21831]

I recently took my 3g in for smog and everything passed but co, had an excessive amount coming out, have done every maintenance thing possible and car runs fine, idles high when cold but drops down. One concern from the begining was the excessive pressure coming out the fuel filler when i pulled off the cap but never looked into it until now that it didnt pass smog cause too much fuel coming out the exhaust. I have a theory that the charcoal canister may be clogged and letting pressure build up in tank or going through engine and out the exhaust, I know the way i described that is loose so anyone help me out and fill me in some things i missed or was wrong with. thanks

[A20A1]

The charcoal canister bleeds fuel vapor back into the carb then the car first strats... Other then that I think the float bowl is vented thru the brass ports extending from the top of the carb.

[dill21831]

So A20 What do you think could be the problem, someone said fuel regulator but i couldnt find that in the manual for carburated, are there any other things that you think would cause too much fuel to be coming out the exhaust besides maybe tuning the car

[HondaBoy]

you said there seemed to be a lot of pressure comming out of the fuel filler after taking the cap off? well this is very normal for a carburated car, and sometimes with fuel injected cars. but thats nothing to worry about. dont know what your problem could be. hope you get that worked out!

[smufguy]

what was the reading of the CO for you? Mine was 5.6% when i failed mine. I got a bottle of Gauranteed to pass emissions and ran it with full gass until empty, got premium, two bottles of gas treatment (Methanol) and new sparkplugs. and i passed.

The gas treatment is most likely Methanol that produces less CO under combustion. Also the sparkplugs on mine were gone. I bumped my fuel pressure to 30psi and new sparkplugs.

The guaranteed to pass emissions is a high density cleaner that cleans ur fuel system really good. Run your car a little lean.

High CO usually means ur running a lil rich and/or having incomplate combustion.

Also check on your Coolent mixture level. 70% is the max and 50% is the min.

[87accordlxph]

I don't think a carb Accord has a fuel pressure regulator.
Fuel pressure comes from the fuel pump if I'm not mistaken.
Anyway, your definately running too rich!
For a high reading of CO.
Lean out the air/fuel mixture by turning the screw at the back of the carb
(near the firewall) it may have a cap that covers the screw.
Turn this screw clockwise to lean the carb.
You should pass after this.
If you need info on how to do this, talk to A20A1 he's got a how to on this.

-Mike from Sarnia!

[smufguy]

fuel pump puts out constant pressure/ volume to prolong its life. chocking of the return line is what gives u the fuel pressure if im not mistaken at the rail. sine fuel regulators are vaccuum operated, its easier

[dill21831]

thanks guys for all the help, how hard is the mixture screw to get to in the back, what would i have to take off to just get in there. im from ca so max on co is .86 at 15 mph and i had a 1.61 and .66 at 25 mph and i pulled in a 1.38. I think the distributor and rotor look kinda past its prime so replace those, went to change the engine coolant and it was so brown i thought i saw rust in it, cleaned out until i saw clear, put new coolant back in but still had some mroe brown in there so ill give it another flushing and just tweak the idle screw a little bit? it runs fine besides i think a bad alternator(light flashes every once and a while)........thanks guys anything else u could think of would help

[dill21831]

not idle screw i meant mixture screw.........

[87accordlxph]

fuel pump puts out constant pressure/ volume to prolong its life. chocking of the return line is what gives u the fuel pressure if im not mistaken at the rail. sine fuel regulators are vaccuum operated, its easier

Thanks smufguy for explaining that! :)
I like instant info w/o doing the research myself.

-Mike from Sarnia!

[87accordlxph]

thanks guys for all the help, how hard is the mixture screw to get to in the back, what would i have to take off to just get in there. im from ca so max on co is .86 at 15 mph and i had a 1.61 and .66 at 25 mph and i pulled in a 1.38. I think the distributor and rotor look kinda past its prime so replace those, went to change the engine coolant and it was so brown i thought i saw rust in it, cleaned out until i saw clear, put new coolant back in but still had some mroe brown in there so ill give it another flushing and just tweak the idle screw a little bit? it runs fine besides i think a bad alternator(light flashes every once and a while)........thanks guys anything else u could think of would help

Check your battery first. Bring it to advanced auto parts or autozone. I think they can put a load on it and test it for free?
The battery light on my ride came on this past winter as well, it might as well be your alternator acting up. Does it make noise like a wizzzz sound sometimes and then it doesn't? I took a hammer and gave the alternator a few taps at the rear of it near the firewall and it temporarly fixes the problem.
It could also be your drive belt, maybe too loose check the deflection on the belt.

For a small tune up, you want to change your spark plugs, plug wires, distributor cap and rotor oh yeah the mechanic will test your fuel system as well so keep the fuel filter clean at all times. You really don't need to replace the distributor unless it has lots of red dust in it when you remove the cap, rotor and dust cap and if you notice a change in ignition timing (your motor will rev up and then down and then this over and over again). Mines to the point where it doesn't idle anymore :( Damn. Pain in the ass.

Changing the coolent was a smart move by what smufguy said, that will lower NOx a bit. Leaning out the carb will raise NOx so... keep the motor cool.
I hope you will pass this next time.
I did lots of extensive testing on all my emmision parts for a pass.
Next time I'll do what smufguy suggested.

Good luck!

-Mike from Sarnia!

[smufguy]

a tune up would help you a lot too. I dont know when the last time u got one, also, dont forget the plugs. How old is your O2 sensors. These things are main faults for high CO.

[dill21831]

Um tune up was just given, and i mean major talkin all fluids and filters......spark plugs, i didnt change the cap and rotor because i was not sure how wore down they were, cant tell the difference.......i mean i do see deposits, but they dont look horrible.........but they probably do need to be changed........i tryed changing the o2 sensor but in the process it was so tight it broke my 5/8 to 3/8 adapter right in 1/2.........so figured maybe it wanted to stay on lol but they said it passed......maybe it does need to be changed.........

as far as the battery being checked ive check it out, it seems fine, my uncle(where i got the car from for free).......said the brushes on the alternator keep burning out, havent had a chance to ask whether thats what he keeps replacing and goes bad, or the whole alternator together.....

[riced_roach]

What the heck does coolant have to do with emissions???? Changing it WILL HAVE ABSOLUTELY NO EFFECT ON NOX READINGS!! Your thermostat regulates engine operating temperature. Man thats a very amusing/interesting statement that is totally false. NOX is caused by many variables: too much advance timing, carbon deposits creating hot spots, defective EGR, Defective/worn out catalytic converter, too lean a/f mixture. If your thermostat is not opening that will cause higher engine temps but changing your coolant (50/50) mix do nothing in operating temps.

If you remove a vacuum signal to a fuel pressure regulator it will pass full pump pressure.

You must have a perfectly operating charging system and battery or this may effect ignition. Having problems with this system can produce a weaker spark possibly.

Tweak the a/f mixture screw. If you tweak too much you may get too lean creating a high HC reading due to lean misfire.

[smufguy]

i dont know what coolant does to NOX, cause it does not do anything to it.

having improper coolant/water mixture will have the engine operating at higher temperature since the raw coolant does not conduct heat or to say transfer heat like a regular distilled water does. This makes heat transfer from the engine to the coolant hard and thereby raises the engine operating temperature. Thats why. :D

[87accordlxph]

i dont know what coolant does to NOX, cause it does not do anything to it.

having improper coolant/water mixture will have the engine operating at higher temperature since the raw coolant does not conduct heat or to say transfer heat like a regular distilled water does. This makes heat transfer from the engine to the coolant hard and thereby raises the engine operating temperature. Thats why. :D

AGREED. It lowers combustion temperatures!
That's another thing to check is the O2 sensor. Check the ECU for codes that's underneath the driver's seat. Try some penetration oil that will help loosen it a bit from the exhaust.
When was it last replaced anyway?
My carbed Accord doesn't have one. :D

-Mike from Sarnia!

[Magny]

I got High NO, everything else passed, except the missing parts that I had stated before. I got all the parts back on, but haven't gone for a recheck yet cause I am afraid of not passing. I wanted to change my O2 sensor first, cause I found out that with my a/f gauge that it is defective. I told my friend to tap the sensor with a hammer while I look at the gauge, and sure enough every time he tapped it, it jumped up, hovered for a few seconds and dropped. So I told him to stop for a sec, then I hit the gas it went up then dropped instantly. So if anything, the sensor that I have has a dysfunction to it. One time it actually stayed up where it normally hits to for like 5 minutes, then dropped when I hit a pot-hole.

[riced_roach]

i dont know what coolant does to NOX, cause it does not do anything to it.

having improper coolant/water mixture will have the engine operating at higher temperature since the raw coolant does not conduct heat or to say transfer heat like a regular distilled water does. This makes heat transfer from the engine to the coolant hard and thereby raises the engine operating temperature. Thats why. :D

NOPE incorrect. The point of antifreeze is that it doesn't freeze at zero degrees and also it changes the boiling point of coolant (water and antifreeze) not only that it also acts as a lubricant for the waterpump. It DOES NOT raise the engines operating temperature!! hmm whats the thermosat for???? Yup its the device that regulates operating temperatures. The combustion of a/f mixture is NOT EFFECTED by the coolant. NOX readings is caused by high temperatures of combusted fuel in the combustion chamber. Coolant DOES NOT change the temperatures of burning a/f mixture being lean or rich. There is absolutely no relation. thats like saying your car failed emissions due to low tire pressure.

distilled water will boil at 100 degrees which will obviously overheat the car which will increase temps. 50/50 mix is usually the standard mix for moderate temp environments.

accords equipped with carbs do not have feedback carburetors. That being the case of course theres no 02 sensor for a NON feedback carb.

[smufguy]

riced roach, you are not seeing this right. The antifreeze does not raise the engine temp or what not, it DOES NOT CONDUCT HEAT as good as water. There is a reason for mixtures to be in the range of 50% to 70% coolant and rest being Water. The reason you are supposed to use Distelled water is to minimize salt formation under continueous above boiling point operation.

Your car thermostat operates under Temperature setting. Lets say your Thermostat would open when the coolant temperature is 180 Degrees and your fan thermoswitch at the bottom of the radiator turns on at the same temperature. When you have more than 70% coolant, it does not do the said things above due to poor heat conduction.

Why do i repeat this? well its cause i have experienced it, I have had about 90% coolant and my car overheated. Dont go by the gauges on the dash, they do not read the actual temperature. When you hook up a thermocouple to the cylinder head, you will automatically know that at this concentration or any above 70% concentration, your car will be operating under "Overheated" Condition without your awareness.

There is no where have i mentioned that the improper coolant will RAISE the engine temp, i said it will make the engine operate under that condition.

Also, more the coolant percentage, the slower it would pass thru the radiator fins. If you ask any mechanic, he would call it as the Radiator Chocking. The high density of the Coolant makes more viscous than a regular water let alone a 50-70% mixture and slows down the coolant in the radiator there by having improper or inadequate cooling of the warmed up coolant.

There is a difference bwt your car just running hot, than your car running hot due to lean conditions. There is a logical difference, read the first line of my previous reply, you will know what i said.

[dill21831]

Um i dont know the last time it was changed, just picked the car up from my uncle about 2 weeks ago and did the normal major over haul, only thing left is new cap and rotor, brake pads to be put on, and the o2 sensor which i could not get off for the life of me......ima big guy and i was torqing it as hard as i could and i could hear the metal from my adapter tweeking.......actually kinda funny that i knew it was happening but didnt think about it, so some penetration oil will help loosen it.......any other type of oil or fluid that will do the same thing to losen it??.......and no you guys, coolant has nothing to do with affection combustion.....

[dill21831]

affecting combustion** I know some things about cars but nothing about spelling

[smufguy]

Um i dont know the last time it was changed, just picked the car up from my uncle about 2 weeks ago and did the normal major over haul, only thing left is new cap and rotor, brake pads to be put on, and the o2 sensor which i could not get off for the life of me......ima big guy and i was torqing it as hard as i could and i could hear the metal from my adapter tweeking.......actually kinda funny that i knew it was happening but didnt think about it, so some penetration oil will help loosen it.......any other type of oil or fluid that will do the same thing to losen it??.......and no you guys, coolant has nothing to do with affection combustion.....

i Forgot to mention this, but use WD40 or Liquid wrench or some kinda on the O2 sensor base and let it sit for a while. Then use a pipe wrench to loosen the sensor. Thats the only way i was able to get my sensor out, Even with a 1/2 drive breaker bar, the thing would not move. It really blows to have a rusty manifold :D

[dill21831]

after putting the wd40 on the o2 sensor how easily did it come out, im sure it still took some work.......how does the rotor come out, just snug on it and it comes out??

[smufguy]

it comes off easy, cause its the pipewrench. U have used pipe wrenches before. They are heavy mofos and they grip like hell. Actually u will see that the place where the socket goes on and locks in on the O2 sensor, the pipe wrench will bite into it, make sure the wrench is tight on it and with a lil push, it turns.

Here is a tip that may sound weird, but works. if its still hard to loosen, try tightening it and then once it clicks turn, then loosen it.

if it still does not work, just light ur car on fire. hhahaha, just kidding, a pipe wrench should help it come off. I have done it, use the 12" pipe wrench tho.

[ELM'sLX+CHL'sDX]

Actually, the cooling system does affect the NOX reading. If you're running too hot, then your NOX will be high. How high of a variance does it have to be before you will fail? That I don't know.

At least on the BMW 8 cylinders (E38 & E39) that I have seen, if the engine is running 5 degrees higher than normal, that car will fail the NOX reading. Now, our 3G Accords may have a higher tolerance, but cooling does affect NOX. You might want to look at your O2 sensors as well.

Claude

[dill21831]

yea i sprayed some wd40 on the sensor tonight....going to let it sit.......spray some more and give it a go.....the battery light comes on when i pull to a stop then after a few seconds it goes away or is there but so lightly its hard 2 tell..........alternator looks new but has trouble with it, battery looks old, what could it be? plus when i push the brake excessively the idle drops bout a 100 rpm, normal?

[dill21831]

yea i sprayed some wd40 on the sensor tonight....going to let it sit.......spray some more and give it a go.....the battery light comes on when i pull to a stop then after a few seconds it goes away or is there but so lightly its hard 2 tell..........alternator looks new but has trouble with it, battery looks old, what could it be? plus when i push the brake excessively the idle drops bout a 100 rpm, normal?

went and got it smogged, vacuum leaks, new o2 sensor, and timing adjustment and it took the test like a champ

[Magny]

well i decided to go to the junk yard and get another header w/o the O2 attached and get the new one attached to it and put the header on. I also put a new cat on too before going to get it tested. The part that sucks is, after doing all that and failing again, the guy says it may be a possible EGR valve malfunction. But I think he is wrong, cause it works perfectly fine, the only thing that I think that prevented the EGR valve from working was a loose hose that wasn't plugged in. So if anything I don't think I needed all that other stuff LOL. Oh well at least I know it will work for another 5+ years with the new parts on it. Still need to go and get it retested to see if I pass now that I know that the hose wasn't attached.

*EDIT*

Oh also, now my car runs a whole lot stronger and plus I have been kickin major butt racing, guess that hose was the main performance problem LOL, or not. But it maes me feel like it has gotten a whole lot faster.

[accord3Gkidd415]

i'm no mechanic and i need some suggestions... i just bought a 3g lx and previous owner failed smog twice. first time they said change cat, but he did this and came back and the car failed once again, but with worser results (almost twice as bad). i don't wan't to smog car again w/ trying to attempt to fix the problems. please help me....

[Mac]

There was just a thread in the Technical section about emissions. It ended up being the O2 sensor. You can test the O2 sensor if you have a volt meter. Disconnect the plug and with the engine running at 5K the voltage should be above 0.6 volts. When throttle is released the voltage should drop to below 0.4 volts.

Do a search and you will find alot more suggestions on failed emissions.