NOx emissions failure- any new wisdom?

[Greg Corcoran]

Colorado changed the NOx requirements in January 2021. This area of Colorado is now under CA IM240 requirements. So this is a 49 state MTX being held to CA standards. My last passing result in 2020 was 2.42 GPM and my failing result yesterday was 2.31. Searching the archives there seems to be nothing on this topic in about 15 years. The old threads suggest: new ECT, new O2 sensors, cleaning MAF (especially if K&N filter is used), adding a few gallons of alcohol, and as a last gasp cheat, unplug the SPOUT connector.
I have my emissions results back to 2016 when I bought the car. The old limit was 2.5000 GPM. In 2016 I had a 1.7812; 2018 2.1278; 2020 2.4204; 2022 2.3066. 2016 was stock Y-pipe, remainder was ShoSource equal length with CATs. In 2021 the limit dropped to 2.0000 from 2.5000 so the 2.31 yesterday would have passed until the last year. Before someone says it - the stock Y-pipe is long gone. It took up too much space and I never dreamed I'd need it again.
Cleaned the MAF last night and replaced the K&N with a paper filter. I have ordered the ECT and O2 sensors from NAPA, should be here today. Or should I be looking for a stock Y-pipe in the Boulder/Denver area? Any other new wisdom in the last 15 years for NOx reduction? I'll sell the car before retrofitting and EGR and changing computers.

 

[Greg Corcoran]

PS - SHOSource no longer seems to sell California CATS. I just looked at their site.

 

[zoomlater]

does pulling the spout connector help with that number

you can try contacting Shosource, they have stuff they don't list on their website or they may know someone who might have one

 

[zoomlater]

One of my cars is a CA delivered car and it doesn't have an EGR installed

 

[NoSlo]

EGR won't really kick in until you are going at highway speeds anyway. Opening it by manual vacuum at idle and you'll see the RPM falter and the engine struggle. They are probably testing at idle, as here they've done away with a dyno roller after mishaps.

A quick look says that it is essentially from too high combustion temperatures, making different products than just water and CO2 out the tailpipe from atmospheric nitrogen. Lean mixture does that.

You can go with a seafoam cylinder cleaning, to decarbon hot spots, letting a little of the stuff at a time get sucked into a vacuum hose at 2k rpm and blowing massive smoke out the tailpipe, or just water. Then an oil change so that uncontaminated oil is coating the cylinder walls.

The O2 sensors might help, but they essentially switch or don't switch. After a MAF cleaning with electrical contact cleaner, and after a new air filter that doesn't restrict and cause less fuel to be learned, do the complete idle relearn procedure on a warm engine. Run the engine and the cats up to super hot with some hill climbing before you go to the emissions center, or park it at 3500RPM for five minutes right before you roll in. And maybe get it tested at the lowest altitude place you can go.

Alcohol will just make the mixture leaner, as it takes more squirt to get to stoch mixture. No ethanol high octane goes the other direction.

 

[Greg Corcoran]

EGR won't really kick in until you are going at highway speeds anyway. Opening it by manual vacuum at idle and you'll see the RPM falter and the engine struggle. They are probably testing at idle, as here they've done away with a dyno roller after mishaps.

No, we still have the IM240 dyno test. They run the car up to 60 mph during part of the test. The woman doing the test was clearly not skilled at manual transmissions as she had a hard time keeping the speed in the required band during the test. I'm sure that didn't help either.

Looking at the printout, the NOx spikes happen during or just after acceleration. So I'd agree with high combustion temps.

I've traded emails w/ Mike at ShoSource since my initial post. There is no good news unless I can find a used CA version of the Magnaflow Y-pipe or pair of last (2nd) generation california Cat. I need to pass the new Colorado limits or get a state issued exemption. To get an exemption I have to spend more than $715 on emission related repairs AND install newest (3rd) generation California CARB/EO convertors. SURPRISE! there are no California compliant convertors being made for Gen 1/Gen 2 (that fit). So there is no exemption possible.

 

[luigisho]

For numbers that low you might have to try and get a spare oem y with cats or get one fabbed with cats that will make it pass. Pulling the spout was always good for a few numbers but not sure if that would be enough currently. Will an oem ypipe fit the rest of teh exhaust? This is new territory since most of these cars weren't designed to meet this standard.

 

[zoomlater]

so these don't meet the latest requirement?

Catalytic Converter California Approved Legal Catco 2.25" / 1995 and older cars | eBay

This is for 1 Catalytic Converter. 1995 and OLDER vehicles. 2.25" inlet and outlet no air tube. ANY ISSUE OF ITEM MUST BE REPORTED WITHIN. < a=""> <>.

www.ebay.com

I would try finding cats from a Gen CA ATX car and weld those on. Try posting in the Want to Buy section to see if anyone has their old pipe laying around

 

[M Brown]

You could have someone weld in new cats, if it still fails this should cover the $715 dollar limit. try these guys https://www.verociousmotorsports.co...-Sport-Ultra-High-Output-Catalytic-Converters

 

[Greg Corcoran]

so these don't meet the latest requirement?

Can't tell if they physically fit or not. They need to be 12" or less inlet to outlet or the back one won't fit in the high flow Y-pipe. No dimensions given in the eBay listing so I pinged the seller.

BUT there is a second piece - CARB has to approve the cat for the application, and in the link to the approvals in the listing no Taurus, SHO or SLO, is listed. That approval (CARB or EO number) only comes into play (in Colorado at least) when you apply for a waiver if you still fail after installing new California spec 3-way cats. I asked Mike @ ShoSource about what CARB or EO number to look for and he said the only one approved for Gen 1/Gen 2 SHO actually does not fit. What do you expect from the people at CARB who just outlawed ICE engines...

 

[Greg Corcoran]

Presuming This is the SPOUT #1 connector, pulling it does not make the car pass NOx emissions. The reason I have doubts is what I presume is SPOUT #1 plug (picture 2) does not look like the picture in the archives. The SPOUT #2 plug under the coil pac looks just like the picture in the archives.
NOx would have failed the old limits with this disconnected. I also installed new O2 (Bosch) and ECT (Eichlin) sensors this weekend and fixed a vacuum leak in the evaporative emission system.... And bled a quart of water through a vacuum port into the intake to decarbon the cylinders.
HC and CO came down, but they passed the first time and did not need to come down. So my takeaway is pulling the SPOUT#1 may fix HC and CO, but clearly makes NOx worse.

emission	1st test	2nd test	NEW limit	old limit
HC	0.6166	0.5049	1.0000	1.2000
CO	7.7929	5.1716	15.0000	15.000
CO2	325.07	378.84	none	none
NOx	2.3066	2.9673	2.0000	2.5000

Also it was 20 degrees cooler outside today when tested (75 vs 95) and instead of waiting in line 30 minutes it was only 15. Both of those should have helped.

 

[luigisho]

Is there egr on that car?

 

[Greg Corcoran]

Is there egr on that car?

No. No evidence it ever was. No hole or plate on intake, X2J computer. Why?

So this is a connector with a plug on it (no wires come out of the plug connector) so if it is not SPOUT #1 I'll dig a little further for another plug once the engine cools off.

 

[luigisho]

Sometimes you can lower emissions a few clicks by changing egr valve if the current one is old. I would say try the HEET trick but I don't think that works for NOx. I think you might need a used ypipe with oem cats or some good cats spliced in to what you have. THat sucks

 

[zoomlater]

did you see the link I posted in your want to buy add, it shows what the spout connector looks like

How to pull the SPOUT connector, With pics.

Ok, so here is a seemingly simple write up on how to pull your SPOUT connector so you can pass your emission / smog test with ease. While the connector is pulled your car will feel like it has a loss of power, and is running with about 100 HP. That is normal when the connector is unplugged. I...

shoforum.com

 

[Greg Corcoran]

did you see the link I posted in your want to buy add, it shows what the spout connector looks like

The Spout 2 I found looks just like the one in your link. I thought this was the SPOUT 1, as I did not see or feel anything else.
I have just come in from the car and it was cool enough to go spelunking a bit deeper and I did find a grey SPOUT jumper and promptly dropped it taking it out. 20 minutes later with the help of a borescope I found it and retrieved it . Guess I'll go for a drive and see what it feels like. I also cleaned and put on a larger MAF I had sitting around on (stalled project from another life).

 

[Greg Corcoran]

No. No evidence it ever was. No hole or plate on intake, X2J computer. Why?

So this is a connector with a plug on it (no wires come out of the plug connector) so if it is not SPOUT #1 I'll dig a little further for another plug once the engine cools off.

Presuming This is the SPOUT #1 connector, pulling it does not make the car pass NOx emissions. The reason I have doubts is what I presume is SPOUT #1 plug (picture 2) does not look like the picture in the archives. The SPOUT #2 plug under the coil pac looks just like the picture in the archives.
NOx would have failed the old limits with this disconnected. I also installed new O2 (Bosch) and ECT (Eichlin) sensors this weekend and fixed a vacuum leak in the evaporative emission system.... And bled a quart of water through a vacuum port into the intake to decarbon the cylinders.
HC and CO came down, but they passed the first time and did not need to come down. So my takeaway is pulling the SPOUT#1 may fix HC and CO, but clearly makes NOx worse.

emission	1st test	2nd test	NEW limit	old limit
HC	0.6166	0.5049	1.0000	1.2000
CO	7.7929	5.1716	15.0000	15.000
CO2	325.07	378.84	none	none
NOx	2.3066	2.9673	2.0000	2.5000

Also it was 20 degrees cooler outside today when tested (75 vs 95) and instead of waiting in line 30 minutes it was only 15. Both of those should have helped.

Passed with the SPOUT#1 pulled and a professional decarboning and injector clean ($191). But I think I'm done. Over $400 bucks and I still had to hobble the engine to pass the new lower limits from the enviro-fascists. You may see this car on Bring a Trailer before too long.

emission	Passing test	prior test	Limits
HC	0.8236	0.5049	1.0000
CO	5.9695	5.1716	15.0000
CO2	442.9798	378.84	none
NOx	1.3497	2.9673	2.0000

 

[luigisho]

You passed with flying colors and figured out how to do it. Education is never free on these things but now you know and you don't have to figure it out again. You're good to go.

 

[zoomlater]

Glad you passed, enjoy the car until the next time you need to test. Then, see if pulling the spout will pass the next time

 

[FastCAD]

Colorado changed the NOx requirements in January 2021. This area of Colorado is now under CA IM240 requirements. So this is a 49 state MTX being held to CA standards. My last passing result in 2020 was 2.42 GPM and my failing result yesterday was 2.31. Searching the archives there seems to be nothing on this topic in about 15 years. The old threads suggest: new ECT, new O2 sensors, cleaning MAF (especially if K&N filter is used), adding a few gallons of alcohol, and as a last gasp cheat, unplug the SPOUT connector.
I have my emissions results back to 2016 when I bought the car. The old limit was 2.5000 GPM. In 2016 I had a 1.7812; 2018 2.1278; 2020 2.4204; 2022 2.3066. 2016 was stock Y-pipe, remainder was ShoSource equal length with CATs. In 2021 the limit dropped to 2.0000 from 2.5000 so the 2.31 yesterday would have passed until the last year. Before someone says it - the stock Y-pipe is long gone. It took up too much space and I never dreamed I'd need it again.
Cleaned the MAF last night and replaced the K&N with a paper filter. I have ordered the ECT and O2 sensors from NAPA, should be here today. Or should I be looking for a stock Y-pipe in the Boulder/Denver area? Any other new wisdom in the last 15 years for NOx reduction? I'll sell the car before retrofitting and EGR and changing computers.

move to florida. no sniffers here.