View Full Version : Vehicle Emissions in Jefferson County
PointBlank82
04-09-2017, 06:19
Anyone got any advice on passing emissions with modified vehicles in Jefferson, County?
Vehicle #1:
2007 Jeep Grand Cherokee with 3.0L Diesel, AWD
Modifications: Green Diesel "Hot" tune, DPF delete & Pipe
In Arizona I got an immediate pass because they didn't have a dyno for AWD vehicles. Same in LA, not sure about CO.
Vehicle #2:
1985 Jeep CJ7 with swapped in 4.0L from a 1994 Jeep Grand Cherokee
Modifications: Custom five-wire fuel injection from Painless (oxygen sensor, cat converter, etc. still intact)
Condition: Light smoke after 10 minute idle. Passed the sniff test in AZ, but failed visual due to lack of out dated "Air Pulse Injection System" original to the 1985 horrible Carter carb system I threw away after the engine swap. Last summer I pulled an air blower from a 90's era Saturn and installed it in a very prominent location and labeled it "Air Blower". Vehicle has not been registered since I lived in OK in 2012 where they didn't care what I drove. (yes I've moved around a lot).
I really want to get the CJ7 street legal without spending anymore money. It's going to be a lot of fun in CO (lifted, locked and geared). The JGC is my daily driver and if forced, I could bolt the DPF back in, but that would be a major PITA as I'd have to reprogram the ECU and change the oil back to European Low Ash Liquid Gold (TM). The 3.0L runs really clean and doesn't need one (they don't even use them in Europe, only here!).
Gonna need that dpf pipe put back and all emission stuff for most counties in colorado on the cherokee.
That cj will have more Le away
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Wasn't Weld one of the ones that didn't have all the extra junk or was easier? Might look into that.
Since diesels are not tested in the state-run testing centers and are tested privately, you could call around see what they say. May find one that is less concerned about what equipment isn't installed and more about results of the test. There are many diesel tuner shops that also do testing.
PointBlank82
04-09-2017, 10:33
Since diesels are not tested in the state-run testing centers and are tested privately, you could call around see what they say. May find one that is less concerned about what equipment isn't installed and more about results of the test. There are many diesel tuner shops that also do testing.
Excellent suggestion. I wonder how hard it will be to find a tester equipped with a dyno setup for AWD...
I don't think the diesel testers do a dyno.
Visual, sniff test, parts, etc.
Mine passes every time, but I only have a box that is set to "factory" when tested and since it's an older diesel, none of the emissions crap. AFAIK, they don't give two shits about the software tunes, just that it passes the numbers.
That said, I think it could be difficult to find one that will give you a pass if you're missing factory equipment like DPF. Their testing license is on the line and they have to meet the State/County reqs.
Like others, I think you might have issues getting the diesel to pass.
The Jeep might be easier because you have to meet 1985 emissions standards which I imagine the newer engine will likely meet. If the "light smoke" is oil burning, I might also suggest changing over to a full synthetic oil. Since full synthetic isn't hydrocarbon based it won't make visible smoke when it burns.
PointBlank82
04-09-2017, 12:30
Like others, I think you might have issues getting the diesel to pass.
The Jeep might be easier because you have to meet 1985 emissions standards which I imagine the newer engine will likely meet. If the "light smoke" is oil burning, I might also suggest changing over to a full synthetic oil. Since full synthetic isn't hydrocarbon based it won't make visible smoke when it burns.
Never heard that about synthetic oil. I have some concerns about making that switch given the age of the engine and possibly dissolving varnish. I finally got it all to stop leaking a couple years ago, hate to go through that again.
I did read on the DMV web page that vehicles 32 years and older can be registered as "collectors vehicles" if they're driven under 4500 miles per year... and then only get tested once every 5 years. hmmm might be worth trying the synthetic option for the test and just replacing before it runs too long.
Great-Kazoo
04-09-2017, 12:35
Wasn't Weld one of the ones that didn't have all the extra junk or was easier? Might look into that.
Negative. All counties doing emissions are the same.
Never heard that about synthetic oil. I have some concerns about making that switch given the age of the engine and possibly dissolving varnish. I finally got it all to stop leaking a couple years ago, hate to go through that again.
I did read on the DMV web page that vehicles 32 years and older can be registered as "collectors vehicles" if they're driven under 4500 miles per year... and then only get tested once every 5 years. hmmm might be worth trying the synthetic option for the test and just replacing before it runs too long.
I suggest you replace the fuel cap, they do a pressure test on it. If it fails, you have to repeat the test.
I suggest you replace the fuel cap, they do a pressure test on it. If it fails, you have to repeat the test.
Are they still doing the cap test? I haven't actually been to one of the emissions places in a while but I heard they no longer test the cap and as long as you don't have any evap codes when they hook up to the vehicle then you're good to go.
The place by my house was always pretty lenient on the gas cap. I had one fail once but they went ahead and passed me but told me I need to go get a new one. Never had any P0440 or 442 codes so I figured they probably just didn't know what they were doing. Went back a couple of years later without ever replacing that cap and it tested good.
Once the OP finally gets all this stuff straightened out I highly recommend making sure to drive through the roadside emissions things so he doesn't have to make a trip to those horrible testing stations.
PointBlank82
04-09-2017, 12:58
Are they still doing the cap test? I haven't actually been to one of the emissions places in a while but I heard they no longer test the cap and as long as you don't have any evap codes when they hook up to the vehicle then you're good to go.
The place by my house was always pretty lenient on the gas cap. I had one fail once but they went ahead and passed me but told me I need to go get a new one. Never had any P0440 or 442 codes so I figured they probably just didn't know what they were doing. Went back a couple of years later without ever replacing that cap and it tested good.
Once the OP finally gets all this stuff straightened out I highly recommend making sure to drive through the roadside emissions things so he doesn't have to make a trip to those horrible testing stations.
Fortunately, the '94 inline six 4.0L is an OBD1 system, so cannot be hooked up to a scanner.
I failed a visual inspection in AZ back in 2012 because they have a screwy rule that all emissions equipment standard to the vehicle needs to be intact.
The only thing my jeep lacked was the pulsed air system which a closed loop fuel injected engine doesn't need. That technology is only used to add excess air to the exhaust to improve the performance of the catalytic converter which suffered on the older carbuerated engines saddled with California mid-80s emissions requirements! The Saturn's used it because their fuel management systems sucked and they ran rich to meet the NOx targets.
Anyways, we'll see how it goes. Thanks for all the great suggestions.
Only part of weld county does emmissions. It stops at Kersey east. Eaton north. But goes to the border with Larimer and adams
I sent the op a pm with the solution
newracer
04-09-2017, 13:41
I don't have any recommendations for the Grand except for what was already said.
For the CJ you will have to have all the emissions equipment from the donor vehicle and it will have to pass the levels for that year. Call one of the emissions technical centers and they can walk you through it.
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Are they still doing the cap test? I haven't actually been to one of the emissions places in a while but I heard they no longer test the cap and as long as you don't have any evap codes when they hook up to the vehicle then you're good to go.
The place by my house was always pretty lenient on the gas cap. I had one fail once but they went ahead and passed me but told me I need to go get a new one. Never had any P0440 or 442 codes so I figured they probably just didn't know what they were doing. Went back a couple of years later without ever replacing that cap and it tested good.
Once the OP finally gets all this stuff straightened out I highly recommend making sure to drive through the roadside emissions things so he doesn't have to make a trip to those horrible testing stations.
My 03 A6 failed the cap test last year due to a visually cracked gasket, but wasn't throwing codes. I borrowed one and passed. Wouldn't be an issue with a drive through pass, so why check? Stupid emissions.
I think I get to skip this year, but have been getting cat warmup codes so I'm concerned that's gonna bite me at some point. However, also getting O2 codes, so maybe fixing that will clear the cat codes, dunno.
Synthetic oil is hydrocarbon based. It's synthesized from natural gas. Synthetic oil also has excellent penetrating abilities. If you think you have oil bypassing now, changing to synthetic will likely make it worse.
Jeffrey Lebowski
04-10-2017, 05:43
Once the OP finally gets all this stuff straightened out I highly recommend making sure to drive through the roadside emissions things so he doesn't have to make a trip to those horrible testing stations.
Huh?
Rapid screen keeps you from having to go to the test stations: http://www.aircarecolorado.com/index.php/rapidscreen/truck-locations/
Testing is based on your address, so if you live in JeffCO, you have to get tested. Yes, they still check caps and if it seems anything other than normal, they do a pretty decent check to make sure you have all the required equipment. Highly unlikely you can pass without a CAT if one is required. The testing locations have AWD capability, so that won't get you a pass. But AirCare CO does not test diesels.
Look here: http://www.aircarecolorado.com/index.php/consumer-information/2015-emissions-inspction-program-faq/ There is a link for Diesel test locations.
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