Failed CO emissions-high CO and HC

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DoubleDingo

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Definitely get it hot, and if your cooling system is good, leave it running while you wait.
 

TurdTaco64

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A good tune up may be all that is necessary, and checking and setting timing. You could probably cheat the carb and lean it out just for the sake of passing emissions. Also, take it for a long drive and get it good and hot before pulling into the test lane, the numbers will be worse the colder the engine is. I'm glad I live somewhere that there is no emissions testing as i'd never pass running 110 octane blended with 93 non ethanol. Lol
Unfortunately the line was about 10 cars long so I was holding the gas the whole time in line. If it was shorter it would have been a lot warmer because it was a 30 mile drive to the nearest testing location that could accomodate 35's. I'm also pretty sure the thermostat is a 175* so that will get swapped before going back in.
Washington used completely different testing standards, PPM HC and percent CO. Sorry for the confusion. I just don't know how high those readings are. The basics still apply, high CO rich, high HC everything else. Do a tune up if needed and lower the CO by leaning the carb out. Many times, high CO will elevate the HC slightly.

Do check that the air pump and cat are working. Combined they are extremely good at emissions reduction.

Harbor Freight has inexpensive heat guns, and they have many other uses.
Yes, after seeing how high CO was I figured it was running rich. Is jetting the only option for leaning out or is there something else I can do? As far as the air pump, it hasn't been connected for god knows how long before I got it, but it at least spins. There is a vacuum line on the actuator for the pump that is capped. I'm wondering if I can force it open full time by running a line to manifold vacuum.
 

fast 99

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Carter carb right? If so, larger primary metering rods. Order a strip kit. May need calipers to measure rods. Again, Harbor freight has inexpensive digital ones. Do a lean drop idle mix adjustment afterward.

If the air pump is disabled that alone could cause the failure. This is an 81 correct? On that vehicle air pumps operate nearly all the time except during decel. That's what the vacuum hookup is for. Yes, you can operate the air pump and not bother with the vacuum hose. However, the decel valve stops the air flow so there isn't a backfire inside the exhaust system. Similar to turning the key off and back on to cause a gunshot noise. It may do that or not.

Sometimes when the air pump systems have been disabled like that the tubes will be melted, check valves burnt up, ect. It may require repair.
 

TurdTaco64

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Carter carb right? If so, larger primary metering rods. Order a strip kit. May need calipers to measure rods. Again, Harbor freight has inexpensive digital ones. Do a lean drop idle mix adjustment afterward.

If the air pump is disabled that alone could cause the failure. This is an 81 correct? On that vehicle air pumps operate nearly all the time except during decel. That's what the vacuum hookup is for. Yes, you can operate the air pump and not bother with the vacuum hose. However, the decel valve stops the air flow so there isn't a backfire inside the exhaust system. Similar to turning the key off and back on to cause a gunshot noise. It may do that or not.

Sometimes when the air pump systems have been disabled like that the tubes will be melted, check valves burnt up, ect. It may require repair.
Yes, Carter AFB which I believe is the same as the Edelbrock Performer? I'll have to confirm and order one of those kits. It's an 86 and just to clarify I got a new belt and reconnected the air pump before testing so it was running during the test. How effectively I can't say but the pump at least wasn't seized. Sounds like I don't need to worry too much about the decel valve unless backfiring gets out of control.
 

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My EGR was clogged, I think they cleaned the passage with a speedometer cable
 

fast 99

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EGR? Didn't fail NOX.

Sounds like it is really inconvenient to make return trips.

Be sure the air pump is working. Remove both hoses running and feel for air. Blow through the check valves make sure they aren't stuck closed or the tubes aren't melted inside manifolds.

Check cat temps.

As I said before they REALLY clean up the exhaust. It may not ever pass without both working. Wish I knew how GPM converted to PPM and %, kind of shooting in the dark on this.

If all is good, then need to address the carb.
 

TurdTaco64

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EGR? Didn't fail NOX.

Sounds like it is really inconvenient to make return trips.

Be sure the air pump is working. Remove both hoses running and feel for air. Blow through the check valves make sure they aren't stuck closed or the tubes aren't melted inside manifolds.

Check cat temps.

As I said before they REALLY clean up the exhaust. It may not ever pass without both working. Wish I knew how GPM converted to PPM and %, kind of shooting in the dark on this.

If all is good, then need to address the carb.
EGR has been MIA since back in 'Nam and I'm 99% sure the Edelbrock intake that's on it now is non-EGR. Ive only had the truck since the beginning of September and haven't had a whole lot of time to get real intimately familiar with it yet because we also took a week long vacation since then. I'll grab an IR gun in the next day or two and check the cat and probably pull hoses off the pump tonight. It is also a bit inconvenient to get to this specific test center unless I downsize tires. That was also a backup plan I had was to throw on a cheap set of CL 31's just for testing. I would imagine lighter/smaller tires would bring emissions down across the board and I could go to the place that's 5 minutes from my house after a nice warmup. Depending what I can get worked out in the next few days I may make another trip up since a retest within 10 calendar days is free.
 

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Welcome from CO. I just moved up here and I'm working on getting my 90 burb emissions compliant. If you ever need a hand wrenching, give me a holler!

I'm not an expert since I'm in your same situation right now, but you'll probably need to put the stock manifold back on, or at least one with an EGR port. Everything I've read so far says the equipment under the hood has to match the sticker. I just put my EGR back on and I'm working on sourcing a new exhaust so i can put a cat back on as well as fixing a leaky injector (tbi).

Also I'm not sure about the tires. smaller tires will raise your RPM's unless you regear.
 

RecklessWOT

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I bought my 'burb in Loveland. I didn't think they were still so strict with emissions? My truck was originally "high altitude emissions" equipped, which AFAIK was something only sold for people in parts of CO (and wherever 85 octane is sold, which like I said I thought was just the CO). Maybe even Cali emissions were not tight enough for your specific test station? Weird because my father has lived in in Loveland for nearly 20 years (Mariana Butte) and I didn't recall him making a big deal out of emissions, he's got some old BS and I really doubt it's all tip-top, I thought you guys were a little more lenient with emissions than some other parts of the state (as long as you don't fart 2mph over the speed limit while driving down Eisenhower lol, maybe the hydrocarbons coming out my ass make a ticket worthy infarction)? In my state my truck is exempt, but if you need any high altitude parts I'm pretty sure I saved almost everything I stripped off. Let me know

Otherwise, I've had good luck in the past (in other states where they're less crazy) getting it good and hot so the cat is cooking like cray. Show up with like a half gallon of fuel still in the tank basically empty, throw in a good half gallon of high percentage rubbing alcohol to dilute it, and let them test away. It might not run great, but alcohol burns pretty darn clean. As soon as you leave, just fill up with real gas again and carry on with life. IDK what your specific ailment it, but I never bothered fixing it just preffered cheating the silly system that shouldn't be there in the first place...
 

TurdTaco64

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Welcome from CO. I just moved up here and I'm working on getting my 90 burb emissions compliant. If you ever need a hand wrenching, give me a holler!

I'm not an expert since I'm in your same situation right now, but you'll probably need to put the stock manifold back on, or at least one with an EGR port. Everything I've read so far says the equipment under the hood has to match the sticker. I just put my EGR back on and I'm working on sourcing a new exhaust so i can put a cat back on as well as fixing a leaky injector (tbi).

Also I'm not sure about the tires. smaller tires will raise your RPM's unless you regear.
Technically yes all original emissions equipment needs to be installed. Did they ever open the hood? Nope. Most of the time they pull out the little inspection mirror and check for cats and I didn't even see that come out this time.
 

TurdTaco64

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I bought my 'burb in Loveland. I didn't think they were still so strict with emissions? My truck was originally "high altitude emissions" equipped, which AFAIK was something only sold for people in parts of CO (and wherever 85 octane is sold, which like I said I thought was just the CO). Maybe even Cali emissions were not tight enough for your specific test station? Weird because my father has lived in in Loveland for nearly 20 years (Mariana Butte) and I didn't recall him making a big deal out of emissions, he's got some old BS and I really doubt it's all tip-top, I thought you guys were a little more lenient with emissions than some other parts of the state (as long as you don't fart 2mph over the speed limit while driving down Eisenhower lol, maybe the hydrocarbons coming out my ass make a ticket worthy infarction)? In my state my truck is exempt, but if you need any high altitude parts I'm pretty sure I saved almost everything I stripped off. Let me know

Otherwise, I've had good luck in the past (in other states where they're less crazy) getting it good and hot so the cat is cooking like cray. Show up with like a half gallon of fuel still in the tank basically empty, throw in a good half gallon of high percentage rubbing alcohol to dilute it, and let them test away. It might not run great, but alcohol burns pretty darn clean. As soon as you leave, just fill up with real gas again and carry on with life. IDK what your specific ailment it, but I never bothered fixing it just preffered cheating the silly system that shouldn't be there in the first place...
Funny you mention Marianna Butts, since that I grew up. My parents have lived there since '97. And 15 years ago emissions laws here were a lot more lax. I could have just tagged this thing with collectors tags and been done with it.
 

fast 99

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I bought my 'burb in Loveland. I didn't think they were still so strict with emissions? My truck was originally "high altitude emissions" equipped, which AFAIK was something only sold for people in parts of CO (and wherever 85 octane is sold, which like I said I thought was just the CO). Maybe even Cali emissions were not tight enough for your specific test station? Weird because my father has lived in in Loveland for nearly 20 years (Mariana Butte) and I didn't recall him making a big deal out of emissions, he's got some old BS and I really doubt it's all tip-top, I thought you guys were a little more lenient with emissions than some other parts of the state (as long as you don't fart 2mph over the speed limit while driving down Eisenhower lol, maybe the hydrocarbons coming out my ass make a ticket worthy infarction)? In my state my truck is exempt, but if you need any high altitude parts I'm pretty sure I saved almost everything I stripped off. Let me know

Otherwise, I've had good luck in the past (in other states where they're less crazy) getting it good and hot so the cat is cooking like cray. Show up with like a half gallon of fuel still in the tank basically empty, throw in a good half gallon of high percentage rubbing alcohol to dilute it, and let them test away. It might not run great, but alcohol burns pretty darn clean. As soon as you leave, just fill up with real gas again and carry on with life. IDK what your specific ailment it, but I never bothered fixing it just preffered cheating the silly system that shouldn't be there in the first place...
Be careful suggesting an obvious illegal activity. This is a public forum.

What you suggest will lean the vehicle out. Go too far, vehicle will fail on HC.
 

DoubleDingo

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Technically yes all original emissions equipment needs to be installed. Did they ever open the hood? Nope. Most of the time they pull out the little inspection mirror and check for cats and I didn't even see that come out this time.
The shop I take my rigs to does the full inspection. He's a Vietnam Vet and a no-nonsense guy, but he is fair and will point out things I need to do. One year he pulled me aside and showed me a rotted hose going to the canister on my jeep, and told me the next time I bring it in it better be fixed. In two years I took it back, and told him I made sure the hose was replaced. The jeep and my 81 have always been easy to pass, only had issues with the 81 this year because of high CO. In my case I replaced the carburetor because I didn't have time to mess around, code enforcement was breathing down my neck and the truck needed the new sticker. You running an AFB, I have no experience with those except removing it and the intake manifold and putting on a spreadbore manifold and a quadrajet. The AFB I had couldn't hold an adjustment for more than a week, I was always tinkering with it because of that. Other than that it ran well and the truck started really easy, tap of the key, easy.
 

Catbox

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Umm...
We pass with empty cats and no pump.
Empty cats for the mirror inspection and the sniffer up the tailpipe passed with flying colors.

That said, I do have a set of 3" cats for when we do the permanent exhaust install.
 

RecklessWOT

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Be careful suggesting an obvious illegal activity. This is a public forum.

What you suggest will lean the vehicle out. Go too far, vehicle will fail on HC.
Oh that's okay, I am more than happy to do illegal things, and I hope others follow suit so these people in charge realize how much of a joke they are. Plus I fail to see how helping someone pass a silly outdated emissions law on a vehicle that should be exempt in the first place would be illegal, if that's wrong then I don't want to be right lol. Heck, I saw someone talk about getting a PO bozx in a town they didn't live in to avoid having to go through emissions, that is more or less "fraud" if you wanna get technical, way worse than what I suggested and I didn't hear anyone crying about that, calm down man. Should I also be afraid to mention spark plug defoulers to get around having cats? I just thought that's what like 90% of people did. Jaywalking is illegal too, but I'm not afaid about that either. I'm not like telling people to go incite violence or something, oh no fudging an emissions test so you don't fail, sorry I forgot this was a public forum I'm now shaking in my boots lol. Dude I would literally have that conversation in the lobby of a police department and not worry about it. It might be illegal on paper but honestly nobody cares one bit. Hah, I also grossly exceed the speed limit from time to time, where I'm guessing you probably slam the brakes when you see that speed sign drop from 65 to 55 on the highway. Should I just quit the internet now or wait till they cart me off in cuffs?
 

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