Emissions help (Ontario)

[xonelith]

Well, I failed my emissions test the other day. I've attached the test results and a scan at idle. Not sure really what to do at this point. I assume the issue is I need a new catalytic converter, but if there is something else that I could do via HPT, to ensure a pass

I also assume that getting the idle to pass will allow for the 25mph test to pass.

My mods can be found on my website, linked in my sig.

I would appreciate any information or tips you could suggest.






Thanks alot!

-xon

[Bill@HPTuners]

Having a cat is really a must for tailpipe emissions & to keep you legal.

[xonelith]

Having a cat is really a must for tailpipe emissions & to keep you legal.

I do have a cat. Hence my question. Do you think my hydrocarbons are out due to my cat needing a replacement? Or would there be another issue, possibly my cam?

Also, if it is the cat, will it help with the CO? Are there any parameters that I could change to ensure a pass, after replacing the cat?

Thanks again!

-xon

[Bill@HPTuners]

How is your afr at idle? I know you have a pretty sizeable cam too which in itself won't lend itself to the best emissions but you have a very small window of afr to be able to pass emissions even with a cat.

[xonelith]

my afr's at idle jump around from 14.2 to 15.2. There's a scan above, but my wideband is before the cat.

idk... maybe crank up my idle to the max (~1100 rpm?) to even it out a bit? the guy at the testing place said that my NO ppm show's i'm running colder. Running hotter should lower the HC somewhat.... increase timing? I also don't want to change the tstat back to stock, (cuz it sucks badly changing that).

I can get a conditional pass, assuming it will cost more than 450 dollars (including diagnosis) to get the car to pass, but I would rather not. I would like to renew my plates in Jan without destroying the environment

[JerryH]

Have you played with idle timing any? This can affect idle hydrocarbon numbers some, but not a great amount.

A radical cam with lots of overlap is going to be a challenge to get to pass without a properly performing catalytic converter.

How many miles do you have on your cat? If its anything over 50,000 miles, you may not have a choice other than replacement.

[xonelith]

Talking to other folks, it seems the hydrocarbons is an issue with oil, not fuel. Apparently I need to look into my PCV (I don't recall ever changing this in 220,000km)?

The cat is not that old, maybe a year (about 50000 km), but i have been bottoming out lately, so maybe I knocked something loose.

On the V6's, at least the GA, I cannot adjust idle timing. Unless I have been misinformed. I would like to adjust idle timing (or at least idle afr).

I'm also thinking that I need to change the plugs (mebbe the minor misfires are throwing off my hydrocarbons; should I use a hotter plug? colder plug? currently I'm 2ranges colder than stock) and clean my air filter. I haven't done these things since the summer.......

Thanks for the info!

-xon

[JerryH]

Talking to other folks, it seems the hydrocarbons is an issue with oil, not fuel. Apparently I need to look into my PCV (I don't recall ever changing this in 220,000km)?

PCVs are very easy to check. If you take them out and shake them, and they make a noise, and you can feel something sliding back and forth easily, they are ok... but with how cheap they are (a few dollars) and how easy it is to replace, I change mine once a year.

Concerning what the abilities of the HPT are, I am as of yet not too familiar with it (I come from a PT background). That will change soon.

[Eddie-98GTP]

The only thing I can think of to help here would be to raise the idle to 1100, set the PCM to stay in open loop, and adjust your AFR at idle to not drop below 14.7. In closed loop, the PCM is going to be trying to get the AFR where it 'thinks' it should be, if you keep it in open loop and adjust your AFR via open loop tables you may be able to squeak by.

BTW = HC ppm = Hydocarbons in Parts Per Million = unburnt fuel (running too rich or lean). Normally high oil usage or PCV problems will cause higher COs.

[JerryH]

Normally high oil usage or PCV problems will cause higher COs.

As could an aggressive cam.

(BTW, nice to see you here Eddie!!)

[MMGT1]

Did you re-enable your EGR or is yours even there anymore? I re-enabled mine and passed the test. Never tested it without it though. Just thought it was a good thing to do. If it actually helped I have no idea, just a thought...My test is during the warmer months too

[xonelith]

From what I've been told, if my NO was high, then fixing (or installing in my case) the EGR will help. Since my NO's are low, I would not expect this to have any effect on my HC, but what do I know...

I think I'll replace my cat, PCV, change my plugs and clean my air filter. Mebbe that will get me by....

Someone on another board mentioned VE tuning, but to my knowledge, during idle, this probably won't help. Is that true? Should I attempt some VE tuning?

Thanks everyone for your input!!

For those interested, here is the info coming from the other post

http://www.grandamgt.com/forum/showthread.php?t=72266


-xon

[Eddie-98GTP]

VE tuning may help, but I don't think it will be enough. With the bigger cam, it's going to idle rich especially when in closed loop. The O2 sensor monitors oxygen level in the exhaust (duh!). With a bigger can (big enough for a rough idle), you will have cylinders that do not fire at lower RPM (Idle). This pushes raw fuel (HC's) and Oxygen (since we didn't burn the fuel, we still have almost 14.7 parts of O2) past the O2 sensor. The biggest problem here is the PCM. The O2 sensor will tell the PCM the engine is running lean (not enough fuel to burn all of the O2), and the PCM adds MORE fuel.

If you could get the PCM to stay in open loop, you could lean out the mixture. The cat I'm sure will help, but it won't last. Raw fuel and high O2 levels will kill a cat pretty fast.

Hope this helps...

BTW - HEY to you too Jerry