Interesting. NICO Stage II ECU vs OEM emissions.

[MinisterofDOOM]

I did emissions/safety inspection today and forgot to switch the ECU back to stock. Failed, switched to OEM, retested and passed with flying colors. Looking at the numbers, though, I found the differences interesting.Also note that these numbers are from a car that is down to two high-flow catalytic converters from the OEM 4. Considering that, especially, I think ALL the numbers except the NICO idle hydrocarbon count look fantastic.All tests were run with a brand new air filter installed minutes before.

OEM results are in BOLD.NICO Stage II results in Italic.

High Speed (2535 RPM and 2535 RPM)-Hydrocarbons (ppm):Standard - 220Reading - 110Reading - 118-CO (%)Standard - 1.20Reading - 0.69Reading - 0.41-CO2 (%)14.114.1

Idle (1133 RPM and 782 RPM)-Hydrocarbons (ppm)Standard - 220Reading - 118Reading - 301 This is what failed.-CO (%)Standard - 1.20Reading - 0.68Reading - 1.00-CO2 (%)14.214.2

So CO emissions are actually LOWER by a respectable amount running NICO Stage II ECU. But hydrocarbon emissions at idle are significantly (over 150%) higher. Interestingly, hdyrocarbon emissions at 2500rpm are nearly identical. Strange.

Also, note the difference in idle RPM between OEM and NICO Stage II. OEM idled unusually high. I wasn't on the shop floor for the test (they wouldn't let me out there) so I'm not sure what the reason for the deviation is. The car doesn't normally idle that high...OEM setting or otherwise. Not sure what the deal is but I wonder if the 400rpm increase played any part in cleaning things up...

[maxnix]

Probably a little more efficient at the higher idle. What's your IAC screw adjusted at?

I know on my OBD I Acura V6 I was advised to let it run at 2500 RPM unloaded immediately before testing.

[elwesso]

makes sense! When we made the NICO ECU we used the JDM idle program instead of the US idle program...

[Q45tech]

Bad Kitty! As most know the charm of JWT, DINAN, ecu was the absolute rule of ZERO tinkering below 2500 rpm so that emission would never be affected.

The problem with changing idle parameters is it cannot be corrected by O2 which never work cold or below 1,000 rpm.

Everything about Idle test is determined by clean injectors, Gasoline composition, MAF, rpm, and the presence of 4 oem cats.

The Law of Unintended Consequences to make for a smoother idle...........JDM IDLE SOFTWARE.

[maxnix]

makes sense! When we made the NICO ECU we used the JDM idle program instead of the US idle program...

More power at idle?

[elwesso]

well makes for a smoother idle, and im kinda convinced it has to do with the lack of precats or OEM cats, because Roberts' car passed emissions with a stage II/III ECU!

[Q45tech]

Those who take the time to study internal combustion engine LEARN that a high CO% is the result of a too low AF ratio , idle is too rich.

Cats only affect HC and Nox [to a small degree].............CATS cannot change CO or CO2 numbers.

Something they will/should teach in high school.

[MinisterofDOOM]

Hey, Dennis, what are your thoughts on Shell's new "nitrogen enriched" gasolines? Sounds to me like a wonderful way to fail your NOx test.

well makes for a smoother idle, and im kinda convinced it has to do with the lack of precats or OEM cats, because Roberts' car passed emissions with a stage II/III ECU!

Yeah, I agree. An 80ppm deviance from tolerance is SO CLOSE to passing that I think having OEM-spec cats would be fine. Even precats with the high-flows would probably be fine.

I hope this doesn't come across as me pointing out flaws in the NICO ECU. I'm just a geek so I saw the numbers and went into geek mode. I LOVE my NICO ECU and the difference it makes in the car. Idle is definitely smoother, so that's worth it for me. And as I noted, non-idle emissions are actually improved (along with the power gains, gapless powerband, better rev limiter and sharper responsiveness) which is awesome. I can tell you I don't spend much time idling in that car. I'd guess that easily 90% of running time is spent above 3000rpm, where the NICO ECU is cleaner.

[Q45tech]

We discussed all this preNICO ecu and why to not fiddle with anything below 2500 rpm.NITROGEN:Marketing companies those that put their brand on PUMPS are always looking for something to fool the 99.999% of the public who are not petrochemical or engine engineers.

Since amines and amides contain NITROGEN in their formula, you could say that every GASOLINE on earth contains an extra amount of Nitrogen [mandated by EPA] as a fuel cleaning and mpg additive. WOW see how dumb marketing people and customers are?

Compounds with the nitrogen atom next to a carbonyl of the structure R-C(=O)NR2 are called amides and have different chemical properties than amines.

[qsiguy]

I would be curious to know how the test would have gone had you just retested without switching programs. Since you just did a test the cats would have been heated up which would have helped the test a bit. The higher idle will definitely change the idle test. In older vehicles when we'd fail we would just turn up the idle a tad and almost always pass.

I just did my first emission test post turbo and major ECU tuning and passed easily. I figured I would have to change back to my stock program but did not. All I did was set my boost controller to stage 1 so if the guy decided to get on it too much he wouldn't high high boost and activate the methanol injection, not that that would have necessarily been a bad thing. I just didn't want to raise any red flags. Here's my numbers...

Hydrocarbons in grams/milestandard 0.80 actual 0.11

Carbon Monoxide in grams/milestandard 12.00 actual 3.03

Oxides of Nitrogen in grams/milestandard 2.00 actual 1.00

I still have all 4 cats, just no resonators or muffler.

EDIT:Was your idle test done in park/neutral or in gear? I looked over the BINs and the only change from stock I can see is the idle speed table in park, no change of the idle speed table in gear.

The idle timing delay is changed from stock both in gear or in neutral/park so that could effect it as well I suppose.
Modified by qsiguy at 9:38 PM 4/28/2009

[Q45tech]

Idle is where the weak ground on MAF showed up and why the auxillary ground was used as a solution. The ground only changes the MAF voltage by 0.05 volts but that is enough when ECU expects 1.10 volts at idle.

The point is each ecu might be a tiny bit different in the digital word it creates from MAF.

Not sure of analog to digital resolution on MAF voltage vs load tables.

[MinisterofDOOM]

I would be curious to know how the test would have gone had you just retested without switching programs. Since you just did a test the cats would have been heated up which would have helped the test a bit.

The car was already up to operating temp before the test. I always drive my cars before testing long enough for them to reach optimal test temps. For the Q I drove around a gear low from normal for a bit to keep the revs up and heat the cats quickly. Probably drove the car for 20 minutes before the first test so I doubt it could have gotten any better from that perspective.

Since amines and amides contain NITROGEN in their formula, you could say that every GASOLINE on earth contains an extra amount of Nitrogen [mandated by EPA] as a fuel cleaning and mpg additive. WOW see how dumb marketing people and customers are?

That's what I thought. I know the PEA in Techron contains nitrogen, but shell's pretty ambiguous as to WHAT the source of the nitrogen is, though, and I can't find an current msds for the gas "with nitrogen".

[mxr662]

Mine passed with the stage II program. I will see if i can find my numbers.

[texasoil]

A high hydrocarbon reading at idle can be caused by old engine oil!!!! .

or partially plugged crankcase ventilation.

Get everything HOT, with fresh oil before next test, AFTER running a tank of premium Chevron + large can of TECHRON

[MinisterofDOOM]

A high hydrocarbon reading at idle can be caused by old engine oil!!!! .

or partially plugged crankcase ventilation.

Get everything HOT, with fresh oil before next test, AFTER running a tank of premium Chevron + large can of TECHRON

Did all of the above. I have a case of techron in the living room and rarely run anything but Chevron premium (shell premium if not). Got the car nice and hot and oil had a few hundred miles on it. I usually keep a 3500 mile OCI, so old oil shouldn't ever be an issue for me.

Mine passed with the stage II program. I will see if i can find my numbers.

Do you have OEM-spec cats? If so, that confirms that my exhaust is the culprit here.

[Q45tech]

Important to actually read injector open time at hot idle:1.1 ms is actually about 0.5 ms of gasoline flow since the injector takes 0.6 to fully open after voltage applied.

1.1 - 0.6 =~ 0.51.2 - 0.6 =~ 0.6

0.6/0.5= 120% MORE fuel not 109% if you 1.2/1.1

Many think that 0.1 milliseconds is not important but it can change AF by 20% causing 14.7 to drop to 11.7 AF.

One total misfiring cylinder [no spark] only increases AF by 12.5% vs 0.1 millisecond error's 20%