Emissions Test= Fail

[Big-J]

Im pissed, now I have to fix something thats going to cost me more money! :banghead:

NOx? Anyone know what this is and how to fix it? Apparently its broken and caused me to fail! :scream1::)

[~Barn~]

Reboot your wireless router.
(inside joke.)

[Nick_Ninja]

Im pissed, now I have to fix something thats going to cost me more money! :banghead:

NOx? Anyone know what this is and how to fix it? Apparently its broken and caused me to fail! :scream1::)

Sounds like an oxygen sensor. They can be replaced by your bad self for around $200

[DavidofColorado]

What kind of car?

Nox is usually caused by high engine temps. In fact I have never heard of anyone failing for that. Its usually CO or HC.

[~Barn~]

Remember when you first bought that truck J-, and it threw a Check Engine light?

If I remember right, when the guy at Adavanced AP checked it (and reset it), it was due to a O2 sensor. Maybe that finally just caught up? :dunno:

[dirkterrell]

NOx is formed inside the combustion chamber when excessive heat is present.

A list of common causes of NOx related smog check failure:
1. As usual check the timing first. Advanced timing can cause extra NOx.


2. The next thing to check is the EGR system.This system is designed to reduce Nox. It consists of a EGR valve, vacuum hoses, one or more vacuum switching valves or solenoids. Its job is to reroute a small amount of exhaust gas back into the engine to help reduce combustion chamber temperature. Not all vehicles have an EGR system.


3. Next thing to check is the air / fuel ratio. If the vehicle is running to lean, NOx emissions will increase.


4. Some possibilities are a restricted fuel filter, low fuel pressure, vacuum leaks, oxygen sensor, load sensor such as a map sensor, air flow meter.


5. Check the cooling system. An extra increase in water temperature will increase NOx production.


6. A defective catalytic converter can also increase NOx. The Cat. reduces NOx that has already been produced.


7. Check to see that the air coming into the engine is not over heated. Some vehicles have a vacuum controlled air valve which switches the incoming air to hot air from the outside of your exhaust manifold.This should only happen when the engine is cold. If this system malfunctions and sends hot air all the time.Your Nox could go up. This system is called T.A.C. ( Thermostatic air cleaner )


8. There is another system similar to the one above called E.F.E. ( Early fuel evaporation ). This system routes hot air under the intake manifold. This helps keep the fuel in the vapor state. If stuck in the hot mode Nox emissions could increase and cause a Smog Check failure.
Link (http://www.smogsearch.com/index.php?page=faq)

Dirk

[Big-J]

I guess my next question would be where to get a diagnositc test done that isn't going to cost me an arm-n-a-leg? Pep Boys want $90, and Im sure a deal is going to want more.

[Kim-n-Dean]

Thankfully, my truck is emission exempt for life!!

Kim's Blazer isn't, so we always change the oil and air cleaner. Our Camaro failed and we changed the oil and it passed. Now, I never go down without doing at least those two things.

Your EGR valve could be stuck too. Or, just need cleaning...

$200 for an O2 sensor?!?!? My Bronco was $30. My Camaro was $25. My buddies 4Runner was $40.

[bulldog]

Finding the broken 02 sensor is another issue, since most cars have a few of them. J I would check 4Runner forums and see if other people have had that same code and how they fixed it: it is usually the easiest way to figure it out. Let me know if you need a hand working on the truck.

[Kim-n-Dean]

Finding the broken 02 sensor is another issue, since most cars have a few of them.I wasn't aware that vehicles have multiple O2 sensors. I've always had just one, just below the exhaust manifold. Usually on the head pipe.

Now, removing can be a bitch because of all the heat cycles!!

[~Barn~]

You would think that you could have a place diagnosis it for $xx, but then apply that, towards the cost of fixing it. :dunno:

For what it's worth, this shop in Brighton replaced my ECT sensor for like $45 bucks, after I purchased and brought in the part. Prestige Audi wanted to charge me like $190 in labor alone. :lol:

It's not your neck of the woods, but if you want to look them up, I think they are called Brighton Auto Clinic.

[DavidofColorado]

If it was me, I would get a free code check again from a auto parts store and if it confirms that your O2 sensor is out. I would change it myself. There is a special socket that looks like a deep walled socket with a side cut out. And replace them. But there is no way to tell if it worked unless you take it back to the emissions place. Or if there is a light and it goes out. But paying a shop to fix it is the easiest but not cheap.

[~Barn~]

Is your truck even throwing an SES code though, or is this just the news that you got, after the emissions place tested you?

I'm guessing it's the latter, because if your ride has an SES light on, I'm pretty sure that's an automatic disqualifier, and they wouldn't have even tested it.

Often times though, OBD II sensors will give you some diagnosis, even if your SES light hasn't been activated yet. They call them "pending" errors".

I got the OBD II at home, if you want to bring it by.

[Kim-n-Dean]

Is your truck even throwing an SES code though, or is this just the news that you got, after the emissions place tested you?

I'm guessing it's the latter, because if your ride is a SES light on, I'm pretty sure that's an automatic disqualifier, and they wouldn't have even tested it. Often times though, OBD II sensors will give you some diagnosis, even if your SES light hasn't been activated yet. They call them "Pending" errors.

I got the OBD II at home, if you want to bring it by.Correct, if the light is on, they won't test it.

Your shop manual will tell you which pins to jump on your diagnostic port to retrieve codes. No scanner needed, usually. Count the flashes, then look up the code.

[brennahm]

^That's OBD 1 not 2. You can blow the ECU by jumping pins on newer cars, not likely, but not worth the risk. SOME new cars (1996 or later) you can turn the ignition on (just turn the key to the on position, don't start the car) three times and then leave it on and it'll either spit out the code on the odometer, or flash the numbers like the old system.

Find a reader, either at a parts store again or Barn. Usually if it's an O2 sensor it'll say which one.

[Big-J]

Kim's Blazer isn't, so we always change the oil and air cleaner. Our Camaro failed and we changed the oil and it passed. Now, I never go down without doing at least those two things.

Your EGR valve could be stuck too. Or, just need cleaning...


I do need ahn oil change and the K&N probably needs to be cleaned, you think this could fix the problem?

[Kim-n-Dean]

^That's OBD 1 not 2. You can blow the ECU by jumping pins on newer cars, not likely, but not worth the risk. SOME new cars (1996 or later) you can turn the ignition on (just turn the key to the on position, don't start the car) three times and then leave it on and it'll either spit out the code on the odometer, or flash the numbers like the old system.

Find a reader, either at a parts store again or Barn. Usually if it's an O2 sensor it'll say which one.
I thought his Toyota was older. I really can't remember, though. If your manual doesn't have a procedure for jumping, then yeah, don't do it!!

[Kim-n-Dean]

I do need ahn oil change and the K&N probably needs to be cleaned, you think this could fix the problem?It very well could. The first two rules to passing an emission test are change the oil and clean or replace the air filter.

[Big-J]

It very well could. The first two rules to passing an emission test are change the oil and clean or replace the air filter.

As you may have noticed, Im not the follow the rules kind of guy! :lol:

[rforsythe]

I wasn't aware that vehicles have multiple O2 sensors. I've always had just one, just below the exhaust manifold. Usually on the head pipe.

Now, removing can be a bitch because of all the heat cycles!!

V-cyl vehicles usually have two, one on each manifold. Some now come with sensors pre and post cat as well. Agreed on getting them off, it can be a real bitch depending on how stuck that thing is.


Now, I never go down without doing at least those two things.

Most guys don't need a checklist for that, but I guess YMMV. :lol:

[~Barn~]

Coincidentally, I just renewed my reg. for my A4, and on the postcard from the Clerk & Recorder's office, it stated that I passed emissions via on-road testing.

First time that's ever happened, and I guess I'm thankful they saved me the time of having to do it myself.

Still charged me the $25 fee though. :lol:

[Kim-n-Dean]

V-cyl vehicles usually have two, one on each manifold. Some now come with sensors pre and post cat as well. Agreed on getting them off, it can be a real bitch depending on how stuck that thing is.
Both the Camaro and Bronco were V8's and they only had one. I've done a lot of work on friends cars and that was always my experience. Granted, I haven't even come close to working on every different vehicle out there. I was just figuring that Jeremy's truck was within my range of experience, perhaps it's not.

Just get a universal Chevy tool (sledge hammer), and fix it!!

[bulldog]

Big-J said he never had a check engine light on, so correct me if I am wrong, but it couldn't be a bad 02 sensor then right? Never heard of a car not throwing a CEL if the 02 sensor is bad.

[Kim-n-Dean]

Coincidentally, I just renewed my reg. for my A4, and on the postcard from the Clerk & Recorder's office, it stated that I passed emissions via on-road testing.

First time that's ever happened, and I guess I'm thankful they saved me the time of having to do it myself.

Still charged me the $25 fee though. :lol:Depending on year, I thought newer cars got a two year period where they were exempt.

[DavidofColorado]

It very well could. The first two rules to passing an emission test are change the oil and clean or replace the air filter.
Or a full tune up just to be safe. Plugs, wires, cap and rotor,(plus coil if its a chevy) o2 sensor~*, oil and filter and lastly air filter. And run a bottle of carb cleaner thru your tank.

*It doesn't always need changed but if your getting shitty mileage it could be bad.

You could change your oil Big-J and take it in to get tested first thing in the morning when its cold out. But then again I don't have all the details like what kinda car you have or your maintenance record.

[Spy007]

I wasn't aware that vehicles have multiple O2 sensors. I've always had just one, just below the exhaust manifold. Usually on the head pipe.

Now, removing can be a bitch because of all the heat cycles!!

Usually 2..

One in front of the cat and one behind it.

[bulldog]

Both the Camaro and Bronco were V8's and they only had one. I've done a lot of work on friends cars and that was always my experience. Granted, I haven't even come close to working on every different vehicle out there. I was just figuring that Jeremy's truck was within my range of experience, perhaps it's not.

Just get a universal Chevy tool (sledge hammer), and fix it!! I have four on my car, one on each manifold, pre and post cat just like Ralph said......

[~Barn~]

Depending on year, I thought newer cars got a two year period where they were exempt.

You're right, but my Audi isn't that new.

[Kim-n-Dean]

I have four on my car, one on each manifold pre and post cat just like Ralph said......Damn! Four! I should update my knowledge!! Never seen one after the cat.

[bulldog]

You're right, but my Audi isn't that new. I actually thought it was four years.


Damn! Four! I should update my knowledge!! Never seen one after the cat. Yeah, well not actually after the cat, but is part of the cat at the rear of it. There are ways to fool your ECU into thinking it is there by using an "anit fowler trick",which is used if you get and aftermarket high flow cat that does not have the 02 bung.

[brennahm]

O2 cylinders will spit codes for a couple different things like no response (wiring is shot) or if there are weird readings coming out. But O2 sensors age and get progressively less effective the older they get. It's actually worth it to replace them at 60-80k miles as I've always seen a mileage increase after doing so. They could just not be working well enough to allow the NOx emissions to increase but not having completely failed.

[~Barn~]

You're right, but my Audi isn't that new.


I actually thought it was four years.

Could be, I don't honestly know. I guess I just meant to say that he was right, regarding the exemption, not how long it's good for.

[DavidofColorado]

Could be, I don't honestly know. I guess I just meant to say that he was right, regarding the exemption, not how long it's good for.
If you buy a car new off the showroom floor. Its exempt for 4 years. If you buy a used car no matter the mileage or year you have to get an emissions test done on it.

If you buy a collectors car with the 5 year plates you have to get emissions once and never again as long as you own it.

[bulldog]

I still don't think Big-J's issue is the 02 sensor since his check engine light is not on.

[TFOGGuys]

Base timing is too far advanced, EGR system is malfunctioning, or fuel mixture is too lean. Oxides of nitrogen only form at very high combustion temperatures, caused by one of the above conditions. Retarding the timing back to stock will usually lose some performance, but should bring the NOx readings back in to line, as well as reducing the CO percentage. High hydrocarbons would indicate a miss, High CO generally indicates a rich condition. I would start with setting the base timing to factory spec using the procedure in your service manual (usually requires jumping a 2 pin connector to disable the computer timing control on Toyotas), and pull the EGR valve to ensure that the passage is not choked with carbon(common on older vehicles).

[Big-J]

Base timing is too far advanced, EGR system is malfunctioning, or fuel mixture is too lean. Oxides of nitrogen only form at very high combustion temperatures, caused by one of the above conditions. Retarding the timing back to stock will usually lose some performance, but should bring the NOx readings back in to line, as well as reducing the CO percentage. High hydrocarbons would indicate a miss, High CO generally indicates a rich condition. I would start with setting the base timing to factory spec using the procedure in your service manual (usually requires jumping a 2 pin connector to disable the computer timing control on Toyotas), and pull the EGR valve to ensure that the passage is not choked with carbon(common on older vehicles).


I can rotate tires, change my oil, brakes, and all that easy stuff, but that sounds way over my head. :|

[~Barn~]

Do you get 1 free retest, J-?

If you do, I would:
- Put in a standard air-filter (instead of bothering to clean/re-oil your K&N).
- Change your oil.
- And pull out your EGR valve, and hit it with carb-cleaner, and reinstall.

I don't know where your EGR valve is on your Runner, but I hear they aren't that hard to get to, and (like Jim said) they often get carbon-caked.

If that doesn't fix it, I'll buy the truck from you for $500; cash, American.

[bulldog]

I have also heard Autozone and places like that sell certain additives you add to help pass emmisions. I know one guy that did it and it worked, but all depends on what code it is that you failed for. J you got a code number or what?

I will up Barn by $5 and offer $505!!! lol

[Big-J]

I have also heard Autozone and places like that sell certain additives you add to help pass emmisions. I know one guy that did it and it worked, but all depends on what code it is that you failed for. J you got a code number or what?

I will up Barn by $5 and offer $505!!! lol


Where would I find the code #?

[~Barn~]

Where would I find the code #?
.

[Big-J]

Then no, I would have to get a diagnostic which was one of my questions.

[bulldog]

Autozone or one of those places will usually run it for free so you get the code that way. Weird the emmision place did not give it to you; did you check your paperwork?

EDIT: now that I think about it this may not work since you do not have a check engine light on. Worth a try though..

[TT5.0]

Did you make sure your vehicle was fully warmed up before you took the test? Here is what I would do:

Fill up the tank minus a gallon or two.
Pump one gallon of E85 into the full tank. ONLY ONE GALLON!
Drive the piss out of it. Shift near redline a lot, blast out the carbon.
When you are at a 1/4 tank, go retest and make sure the vehicle is plenty warmed up before you test.

[Jim_Vess]

I wasn't aware that vehicles have multiple O2 sensors. I've always had just one, just below the exhaust manifold. Usually on the head pipe.

Now, removing can be a bitch because of all the heat cycles!!

The trick to getting the O2 sensor out is to remove it when the manifold is hot. It will usually come out without much effort.

[Scer]

The trick to getting the O2 sensor out is to remove it when the manifold is hot. It will usually come out without much effort.


Your skin will burn off a lot faster too. =P

J, I might have a solution to your problem. Hit me up later.

burn on burnas

[Gramps]

This thread is amusing.........

Firstly, I love when Barn tries to give auto advice. He admittedly knows nothing about automobiles. I know first hand. (Barn you are a great guy, just not a car guy)

:lol:


Second, there are so many misconceptions about vehicle diagnostics it's just funny.


OK......


start from scratch Big -J


what year is your vehicle? Pre 96 is OBD I Post 96 is OBD II (usually)

NOx testing is something that CO just implemented. Huge revenue source and a way to get older vehicles off the road.

Don't take a vehicle to a free diagnostic check place such as Autozone or Checker.(No offense to anyone who works there) They just are not properly trained to diagnose a vehicle.

Look at it this way. You have an upset stomach and you go to the doctor. He says yep upset stomach, lets do a stomach transplant.(notsure thats possible , just making a point.) Doesn't sound right does it. Same theory applies here. Oxygen sensor codes do not necessarily mean that the Oxygen sensor is bad. It just means that it is sensing something out of it factory parameters. It is actually, in most cases doing exactly what it was meant to do. Tell you when something is wrong.

So don't go throw good money at false information.


What year is it?

[~Barn~]

Come on now Tom. A boy can dream, can't he! :lol:

And plus, I hardly ever get to use my Gameboy.. er... OBD II handheld.

[Tipys]

The only thing I would have autozone do is scan and get the code numbers. Also by no means let them clear the codes just in case it needs to be taken to the shop. Also dont let them tell you what they think the problem is they are in the beissness of selling parts not fixing cars. (you dont want to just throw parts at it most likey wont fix the problem and will cost you more in the end likey)


Also the check engine light only will come on after 2 set violations ocurr in a set amount of time and then it can still clear itself out. However if it is a type 1 misfire it will come on right away.

TFOG had the best advice the timing is most likey the issue. (Without looking at it cant be sure) Paying for them to put it on an engine scope is your best bet. Which is what they would use to dianose it. That 90 dollars is the shop houry rate which is about aveage not likey to find much cheaper then that. Yes a dealer ship it will be alot more.

[ChrisCBX]

The trick to getting the O2 sensor out is to remove it when the manifold is hot. It will usually come out without much effort.

I just switched to a high performance exhaust on my Tundra. It has 4, O2 sensors. 2 of them had to be removed and installed in the new headers. I was very surprised how easy they came out. Soaked the threads with WD40. I had read on another forum that this could be a problem area (for my truck at least) due to damaged O2 sensor threads.

[Gramps]

The only thing I would have autozone do is scan and get the code numbers. Also by no means let them clear the codes just in case it needs to be taken to the shop. Also dont let them tell you what they think the problem is they are in the beissness of selling parts not fixing cars. (you dont want to just throw parts at it most likey wont fix the problem and will cost you more in the end likey)


Also the check engine light only will come on after 2 set violations ocurr in a set amount of time and then it can still clear itself out. However if it is a type 1 misfire it will come on right away.

TFOG had the best advice the timing is most likey the issue. (Without looking at it cant be sure) Paying for them to put it on an engine scope is your best bet. Which is what they would use to dianose it. That 90 dollars is the shop houry rate which is about aveage not likey to find much cheaper then that. Yes a dealer ship it will be alot more.


Dude you have some things right and some things wrong. maybe you have more info about the vehicle than I do:dunno:

Your advice about the Zone or Checkers or whoever is fine except there may be more than 1 code. There is also a nice little set of info that is called Mode 6 data that could be helpful in this situation.

Your statement about when and if the mill lights are on or off is only valid in certain situations and only on OBD II

Big -j-

Take the truck to someone who knows what they are doing. it will probably save you money in the long run.

[Gramps]

Come on now Tom. A boy can dream, can't he! :lol:


I'm sure your dreams are interesting :)

[Big-J]

What year is it?

99 4Runner, V6, 4x4

I was thinking about giving Curtis a call and seeing what Stans can do for me.

[Mel]

My dad could give you a couple places to start looking for the issue (most common causes, etc) over the phone (he works for the state of colorado on problem things for emissions, so technically it's part of his job). You should have 10 days on the free re-test, after that it'll cost you...however, if it takes you longer than 10 days to get it fixed or looked at, you could probably have my dad run it and make sure it's all good before you drop the $$ on another test.

Richard(Dick) would also hook you up with the work getting done if you wanted (believe me, he's had to fix issues like this more than once, ahem Snowman :-p)


Also, a code scanner is only going to tell you IF there is a code (i.e. the car sees the issue, which, with no CEL, it sounds like it isn't)...you need to have someone with a real scanner (think $7K cost machines +) which can also tell you readings at mass air, injector on times, fuel mixtures, O2 readings, etc. Richard has a decent one, and my dad has one at his office that they use there on all the vehicles with these same problems.

[Gramps]

99 4Runner, V6, 4x4

I was thinking about giving Curtis a call and seeing what Stans can do for me.


Curtis hasn't been at Stan's for probably a year now. Probably won't do you much good.

:dunno:


99 = OBD II

There are a few things to check on those vehicles.

Has the motor ever had a valve job or had the heads done. If so and they had the heads planed they shortned the combustion chamber causing the pistons to build carbon. Increasing the NO gases.

That motor also has EGR tubes. Check to make sure they are clean.

Also check for vaccum leaks. If it has a vacuum leak then it causes a lean fuel mixture(Tfog was on the right track) which trows off the NO gases.

Check the simple stuff first. Vacuum leaks and fuel pressure. Low fuel pressure could cause the motor to throw off the NOx reading as well.


Hope this points you in the right direction.

Tom-

[Big-J]

Ha! I think I knew that...his family still owns the place though right? Im sure he still has some pull.

Anyway thanks for the info Tom, I'll check for vaccum leaks, tubes and all that good stuff. The engine has never been modified, so I think I good tune up should take care of the problem.

[Speedwagon]

Depending on how much you really want to fix, you can run a 50/50 mix of E85/regular, and will likely pass emissions. And yes, it really does work. I do believe it will reduce CO and NOx emissions both(I KNOW it reduces CO).

[DavidofColorado]

Depending on how much you really want to fix, you can run a 50/50 mix of E85/regular, and will likely pass emissions. And yes, it really does work. I do believe it will reduce CO and NOx emissions both(I KNOW it reduces CO).
The emissions place doesn't test for burning alcohol. They only test for Carbon Monoxide, Nitris Oxide and Hydro Carbons. There is a visual test for smoke. So you could fill your tank with e85 and it will lower your emissions for CO, HC. I don't know if it will effect NOx though? I should. But I would suggest to big j to do a tune up and have it tested again then do the other thing.
Can you post a picture of your VECI sticker Big J? Its under the hood either by the radiator or on the hood itself. But it says Vehicle Emission Control Information. If a tune up doesn't fix the problem that information could prove useful in diagnosing the problem later.

[TT5.0]

Running a high % mix of E85 will lean your tune excessively. That is why I recommend running just a gallon through. I still recommend the advice below, and for the cost of a tank of gas, you can't go wrong. However, a simple tune up will probably fix the problem anyway, and should be done.



Did you make sure your vehicle was fully warmed up before you took the test? Here is what I would do:

Fill up the tank minus a gallon or two.
Pump one gallon of E85 into the full tank. ONLY ONE GALLON!
Drive the piss out of it. Shift near redline a lot, blast out the carbon.
When you are at a 1/4 tank, go retest and make sure the vehicle is plenty warmed up before you test.

[Tipys]

Dude you have some things right and some things wrong. maybe you have more info about the vehicle than I do:dunno:

Your advice about the Zone or Checkers or whoever is fine except there may be more than 1 code. There is also a nice little set of info that is called Mode 6 data that could be helpful in this situation.

Your statement about when and if the mill lights are on or off is only valid in certain situations and only on OBD II

Big -j-

Take the truck to someone who knows what they are doing. it will probably save you money in the long run.


Ya all I know is OBD-2. The things I wrote were right to me but thats because its not the simplest thing for me to explan writing it down or telling someone else how to do it. I cant wait till OBD-3 comes out thats gonna fuck me up in all kinds of ways.

[Gramps]

Ya all I know is OBD-2. The things I wrote were right to me but thats because its not the simplest thing for me to explan writing it down or telling someone else how to do it. I cant wait till OBD-3 comes out thats gonna fuck me up in all kinds of ways.


It's already been implemented in select vehicles.


:)

[Gramps]

Ha! I think I knew that...his family still owns the place though right? Im sure he still has some pull.


Probably less than one would think. But maybe:dunno: