TGP failed emissions test on NOx **PASSED**

[GOT2B GM]

Took the TGP to get emissions tested today, seeing as my birthday is on Thursday and I need to renew my plates.

Here are the results:

ASM2525 Test

     Limit        Reading

HC    58             6
CO    0.32         0.20
NO    652          710


What am I looking at to get this thing to pass the NOx test?

Could this be related to my fuel cutting/stuttering under 7+ psi of boost?

Any help is appreciated.

[GutlessSupreme]

Could this be related to my fuel cutting/stuttering under 7+ psi of boost?

absolutely could be.

I searched quick and found this. it's for an accord, but it explains reasons for high NOx readings. I dunno what your EGR situation is but from what I've seen, it's not usually a problem on W's (it is on '90s Hondas though..) if you have your EGR off, it certainly is contributing to it though.
http://www.asashop.org/autoinc/oct2004/techtips.htm

[GutlessSupreme]

I wonder if your EGR pipe is cracked? if the engine's expecting the EGR to be open, obviously it's running off a different tune.. could potentially be causing timing/burn problems?

anyone else's thoughts on this?

[GOT2B GM]

as far as I know, the EGR valve was not disabled in the chip,  but I'd have to confirm with Kenny to be sure.

I do have the stock plugs gapped tighter than stock (.028" vs. .045") Would that cause excessive heat in the combustion chamber?

Thanks for the replies.

[GutlessSupreme]

as far as I know, the EGR valve was not disabled in the chip,  but I'd have to confirm with Kenny to be sure.

I do have the stock plugs gapped tighter than stock (.028" vs. .045") Would that cause excessive heat in the combustion chamber?

Thanks for the replies.

I'm not going to claim I know a lot about this, but I believe a larger gap would cause it to run hotter, as it wouldn't be burning as efficiently. The gap is right for the tune, but I can't pretend to speak for kenny on whether or not his tune would pass emissions. I guess it has to, if it's supposed to be any better than the stock tune lol. But with that in mind, if you can't figure anything else out, I might swap in the stock chip for the inspection.

[GOT2B GM]

I don't have a stock chip, but I do have a Jeff M TG160.......

Does anyone have a stock chip lying around they'd be willing to sell me for cheap?

Kenny........your thoughts?

[GOT2B GM]

And to reply to your comment above Tony, if the EGR pipe was cracked, wouldn't there be an audible exhaust leak?

I'm thinking of at least taking the EGR valve off and cleaning it and the related ports in the plenum.

[R Dubya]

I'm pretty sure I can round up a stock chip. 


edit: yeah I have one.  I can probably get to it tomorrow but I won't be able to ship it until Wed.  Let me know if you want to borrow it. 

ryan.e.warren(at)gmail.com

[GOT2B GM]

PM sent

[mfewtrail]

Your studdering under 7psi boost and those high NOx could potentially be related. Running lean can cause high NOx emissions. I would consider doing some more fuel related tests to see if your pump is supplying an adequate amount of fuel. Here's a link regarding fuel pump diagnosis.

http://www.aa1car.com/library/fuel_pump_diagnose.htm

Just for what it's worth, my TGP only had 10ppm NOx emissions back in 2002 when it was tested. It was still on the stock chip then. The car was ran @ 1200rpms and the allowable level was something like 1190ppm on that test.

[GutlessSupreme]

Your studdering under 7psi boost and those high NOx could potentially be related. Running lean can cause high NOx emissions. I would consider doing some more fuel related tests to see if your pump is supplying an adequate amount of fuel.

I'll agree with Matt, I might have been quick to mention the chip. Kenny tuned the chip and it ran fine, obviously there's still another issue at hand that's a more likely culprit.

[GOT2B GM]

It does seem like the two issues are related.

Is the Walbro pump the recommended replacement pump?

What is the Walbro part number?

[R Dubya]

how much is does it cost you to have it checked? 


I can ship that to you on Wednesday if you like.  Let me know if you definitely want to go that route tonite.  I'll check back after school and see if I can get it out tomorrow.

[TGPilot]

When I had issues here in Colorado with my red TGP passing emmissions I tried many things to get her to pass. What finally got her to pass properly was a new set of injectors. I had done the fuel pump (Walbro), FPR, filter, and I even ran some dry gas (methanol additive) to try to clear her up to just make emissions. Hell she even had a cat on her with all the emissions turned on.

I replaced the fuel injectors with the yellow top fords from fiveOmotorsports and it was so clean they thought the probe was not positioned properly. They put her in the right side pipe and it was two points cleaner there. I am literally talking a SINGLE digit HC and NO reading.

Do they do a loaded test or is it one of those "in neutral idle for 1 minute, rev to 2500 for 1 minute, then return to idle tests?" Can they give you a break down of the readings to see where it is doing what it is doing?

[TGPilot]

I do not know what the hell I did...but somehow I deleted your last post Matt. Please re-write it.

I think I'm going to try it tonight with the TG160 and my new wires if I get it all together before they close tonight.

If you don't mind I'd still like to try it with the OEM chip to see what difference it makes.

Dude I would try every chip I had on hand. You are not going to hurt my feelings.  ;)

I have sold more than 50 of these chips across the US and have not had one complaint about failing emissions. You will be the first, but it does not mean you will be the only one. This is just the first one i have heard of.  ;)

Let me know how things work out.