OK i just failed Emissions, The only thing I failed was with NOX. I passed the visual, they didnt notice i had removed the cannister but i failed badly in Nox.

Max allowed: 767 at 15mph and 706 at 25 mph
Measured: 2049 at 15 mph and 1870 at 25mph

My Catco cat has only about 10,000 miles on it and I had replaced oil, O2 sensor, distributor cap and rotor, plugs, plug wires, and EGR valve about 2 weeks before i took the test.

Does Charcoal Cannister affect NOX gases?

 

The Charcoal Canister is used to vent and direct the vapors from the fuel tank into the engine to be burned. Those vapors are Hydorcarbons, unburned fuel. The EGR system is mostly used the combat NOX, oxides of nitrogen.

Now I don't claim to be an emissions expert, actually, I don't even have any emission equipment on my car. Gotta love Florida.

Anyway, does your EGR system operate? I assume you will assume it will because you didn't mention any problems or concerns, plus you passed visual.

How about that Cat. I know that there are different cats sold to convert different things. Again, I don't know too much about that because I have never really needed to.

What about your engine itself? NOX is created when the combustion chambers get very hot. High compression and excessive carbon build up can cause that.

Hope this is helpful...

 

I need to check if EGR is functioning correctly, what else should i check?

when I took the Emissions test, I noticed the car was just over 220*F, should I take it next time at a colder temperature?


by the way my HC and CO passed easily:

HC: max 108, measured 79 at 15 mph
max 83, measured 64 at 25 mph

Co: max .71, measured .03 at 15 mph
max .58, measured .02 at 25 mph

Would these results rule out the cat?

 

I wish I could offer anything further than just engine theory, but I don't have any emission testing experience. Sorry. I hope someone else chimes in here to help out.

 

TTT

 

there is a lot to check. missing that bad probably isnt just the EGR. check the timing. and also, it can be a lean misfire.

 

Timing is fine..Lean Misfire? How do I check for that?

 

You don't have misfire with HC readings of 79
Your problem might be the EGR solenoid, they do get stuck sometimes. Take it off and clean it with carb cleaner spray and test it with 12 volts to see if it clicks. Make sure the vacuum lines are not broke going to it.

 

cat is on its way out...


the more complete the burn,. the more NOX's will be produced, likewise, the more incomplete the burn, the more CO will be produced... when ever i failed (which was always for nox's) i've just replaced the cat and gotten through fine... obviously this was different vehciles that i replaced cats on, but they were all old, and even though in tact, they were apparently just not up the operating as well as they were suppsoed to.

 

My Catco cat has only about 10,000 miles on it

 

can it still be the cat?

 

well, only 10k doesnt seem right for a cat to be cooked, espcially since i had a catco cat on for over 50k and it was fine...

sorry dude, only thing i can think of is maybe a bit too lean on the mixture?

the way i explained it was how it has been explained to me by a few different mechanics when i was trying to figuer out how to get my past cars to pass.

try putting a couple containors of alchol in there

 

I forgot to mention I have an Exhaust leak.
Can an exhaust leak cause my car to run lean?

 

depending on where its at, if its before your 02 sensor it could defently cause a lean condition..

 

Dump some alky in the tank when you go in for a retest.

 

my exhaust leak is in the passenger side., my o2 sensor is in drivers side.

Rubbing Alcohol? whole bottle? On a full tank?

 

We run on the dyno over here in NJ, too. I usually put in a bottle of "Guaranteed to Pass", sold at the local Pep Boys for $8. Besides being an all-around (or so they claim!) fuel injector and valve deposit cleaner, it's also supposed to clean the cat somehow.

I've even seen bottles on the shelves that just claim to clean the cat "to get rid of rotten egg smell". Maybe your catalytic pellet bed glazed over; were you running rich at one point? (Fuel beats up the pellet bed). I don't know if any of these chemicals are worth anything, never used the "cat-cleaner-only", but so far I've always passed the dyno with the G2P bottle, so I'll keep buying it.

While you're at it, you might want to do some extra work to the car... throw in a new & cheap air filter, remove the dist cap & rotor and file off all carbon tracking from the terminals with a small flat file (but don't file the terminals at an angle!!), change the $2 PCV valve, etc. When I go, I also pull the plugs, clean them, and check the gap. Finally I check each spark plug wire to make sure all their resistances are within spec (that one wire isn't too far out of spec to cause a misfire).

Hopefully the EGR passageway is just clogged up with a lot of carbon!

 

I thought it was the other way around. I thought it took the air fuel mixture in the intake after you shut your car off and condenssed the fuel out of it and returned it to the tank. Isn't that why there is a connection to the return line on the canistor. I may be wrong but isn't there always fumes in the gas tank. I could be wrong and I am sure someone can set me straight.