lol lucky you colorado springs is done with it.! 
need (CO) emission help fellas!
need (CO) emission help fellas! so in denver its a mandatory thing to get sniffed! and my car has a little work done to it, a pretty aggressive camshaft and full exhaust. The driver side cat is burned out and needs replacing but I took her in to see how bad she did anyway without any help of cleaning the carbon out with sea foam or anything.. I failed the Hydro carbon test kind of bad 4.2 and the limit is 1.2 so what do you guys think I should do? obviously a new set of cats but should I get a tune to just pass emissions or any help would be awesome! I just wonder about other colorado folk passing emissions and how!
Last edited by dub.ya.es.SICK; Jan 25, 2008 at 11:03 AM. Reason: misprint
If it's an idle HC reading then you want to raise up your idle
to lessen the unburnt fuel/air into the exhaust through the
overlap period of the cam. Force your AIR pump to run the
whole time maybe, if you have it hooked up, so the cats can
bust down the HCs with more to work with. May temporarily
wrap the MAC primaries forward of the cats to get maximum
heat at the cats (and O2s). Hotter O2s swing faster and can
keep the mixture tighter-to-center. Run a hot plug and a
factory gap to get best ignition. Change your oil and chase
it out of the manifold / PCV lines, maybe run a thicker oil to
cut burning.
Dunno about your tuning options, having to tune it twice
(once for smog and once for back-to-normal) might suck
for expense.
to lessen the unburnt fuel/air into the exhaust through the
overlap period of the cam. Force your AIR pump to run the
whole time maybe, if you have it hooked up, so the cats can
bust down the HCs with more to work with. May temporarily
wrap the MAC primaries forward of the cats to get maximum
heat at the cats (and O2s). Hotter O2s swing faster and can
keep the mixture tighter-to-center. Run a hot plug and a
factory gap to get best ignition. Change your oil and chase
it out of the manifold / PCV lines, maybe run a thicker oil to
cut burning.
Dunno about your tuning options, having to tune it twice
(once for smog and once for back-to-normal) might suck
for expense.
TECH Enthusiast
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From: Denver International Airport, Colorado USA
To specifically answer your question about "is it mandatory in Denver to get an emissions test".
The answer is yes. And it is getting tougher to pass. Remember, the city of Denver is now utilizing their mobile AIR sniffers at various locations around town.
So, you could just be driving normally and if they scan your car and it's "dirty", you'll get a notice in the mail to test, fix, or get fined.
Several options. Do what Jimmyblue advised. Get a waiver (you must spend at least $750.00 in repairs first).
Luckily I have family and property in Colorado Springs. Check out your ability to legally register the car outside of the Denver Metropolitan area.
While emissions testing is not as tough as California, it is getting close.
Good luck..WeathermanShawn.
The answer is yes. And it is getting tougher to pass. Remember, the city of Denver is now utilizing their mobile AIR sniffers at various locations around town.
So, you could just be driving normally and if they scan your car and it's "dirty", you'll get a notice in the mail to test, fix, or get fined.
Several options. Do what Jimmyblue advised. Get a waiver (you must spend at least $750.00 in repairs first).
Luckily I have family and property in Colorado Springs. Check out your ability to legally register the car outside of the Denver Metropolitan area.
While emissions testing is not as tough as California, it is getting close.
Good luck..WeathermanShawn.
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First off, how are they testing? Idle? On the rollers?
Second, did you fail for CO, or HCs or both? Your title says CO, and in your text you said hydrocarbons. Although the unit of measurement you stated is for CO.
So, all that being said, if it failed for CO, that means it rich. Too much fuel, pure and simple.
You may have contaminated oil, but basically you need to reduce the amount of fuel to air if its high in CO.
Now, you can have high HCs and not be rich. This is the case if you have a cam with overlap. In that case you get unburned and half burned hydrocarbons in the exhaust. But, you can have high HCs and low CO. If its tuned properly.
You can also have high HCs if you have a lean miss.
BTW, running the AIR pump will help a bunch to clean it up, but be warned, it will also cause the converter to run really freegin hot if theres already an excess amount of CO, or fuel.
Second, did you fail for CO, or HCs or both? Your title says CO, and in your text you said hydrocarbons. Although the unit of measurement you stated is for CO.
So, all that being said, if it failed for CO, that means it rich. Too much fuel, pure and simple.
You may have contaminated oil, but basically you need to reduce the amount of fuel to air if its high in CO.
Now, you can have high HCs and not be rich. This is the case if you have a cam with overlap. In that case you get unburned and half burned hydrocarbons in the exhaust. But, you can have high HCs and low CO. If its tuned properly.
You can also have high HCs if you have a lean miss.
BTW, running the AIR pump will help a bunch to clean it up, but be warned, it will also cause the converter to run really freegin hot if theres already an excess amount of CO, or fuel.
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thanks guys, im registering it in fairplay i think and also the CO was for colorado sorry not carbon monoxide and it has low CO and high HC I was thinking of seafoaming it running injecter cleaner new tr55's at .060 and if possible raising my idle.. i have 8 more days for a free test i might as well try it before i register it elsewhere.
one of the crappy things is i have one bad cat on the driver side but they are expensive to be put it.. more than my whole TD setup..exhaust pros quoted 600 i might look around though.. lol damn sniffer tests
By some car sound Magnaflow cats for $50ish off the net and have them welded in...Should run around $150-$200 TOTAL!
What size cam do you run. Getting a car to pass with 0 or positive overlap is very tough to do. If your cam has negative overlap you have a chance. Raise your idle a bit and get the tune to run dead on 14.7 at the speed they test at (idle or MPG). Ours is 25 MPH. If the car runs at stoich at 23~27 MPH you'll have a good chance of passing the roller test. If it runs lean you'll fail NoX and rich will fail HC.