Date: Thu, 6 Dec 2007 09:02:45 -0500
Reply-To: John Brigstocke <jbrig@HSFX.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Brigstocke <jbrig@HSFX.CA>
Subject: Fw: Emissions failures make me feel like a failure
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Wouldn't adding alcohol weaken the mixture - increasing NOx emission?
John
----- Original Message -----
From: "mordo" <helmut.blong@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, December 06, 2007 8:38 AM
Subject: Emissions failures make me feel like a failure
> Thanks for the input, people. I am interested to know more abnout
> standards
> around the country too. I'll search for some compendium of standards at my
> leisure.
>
> A few more items of note:
>
>
> 1. I am suspicious of a leak at the front of the cat - I'm not sure I
> got a good seal there even with two gaskets. I cannot detect a leak but
> the
> flanges are not parallel.
> 2. I had a light 1/4 tank of fuel when I went to test. I added about a
> liter of denatured alcohol just before driving 5 miles to the test
> station.
> 3. The engine was as hot as it ever gets without the fan coming on -
> just at the top of the LED.
> 4. It was about 30F and snowing at the time.
> 5. The exhuast pipe hose at the test station was almost flat - I don't
> know whether more flow or less would be better for my circumstance. The
> marginally intelligent woman operating it said "it don't matter."
> 6. The emissions test station literature suggests high NOx can be
> caused by a lean burn just as some of you suggest. However, the mix
> *seems*
> rich to me. Maybe a raw gas smell at the rear of the van suggests a tiny
> leak somewhere rather than a rich mixture? I certainly can't find a
> leak.
> 7. I have a spare ECU. Any point in swapping that out to see if it
> affects the running condition?
> 8. Is the typical mechanic equipped with any test devices that can
> measure what the emissions test station is measuring? I'd like to
> pre-test
> before going back.
>
> cheers,
>
>
>
> ---------- Forwarded message ----------
> From: Scott Daniel - Shazam <scottdaniel@turbovans.com>
> Date: Dec 6, 2007 2:12 AM
> Subject: Re: Emissions failures make me feel like a failure
> To: vanagon@gerry.vanagon.com
>
>
> Other tips for passing -
> You want it as warm as you can get it. Keep it running the whole time,
> I'm
> not suggesting this, but disconnecting the rad fan sender will get it
> really
> warm temporarily at idle !
>
> Multi-electrode spark plugs - I have read of people reducing emissions
> for
> a smog test using those.
> I 'think' as you retard on timing NOx goes down, but too far and other
> things go back up.
> Always consider 'lean misfire' too as a cause of failing emissions
> results.
>
> Not sure what to do about it, but I've heard that mentioned many times.
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Tabe Johnson
> Sent: Wednesday, December 05, 2007 7:54 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Emissions failures make me feel like a failure
>
> Your chart came out kinda funky on my screen, but it looks like
> you're failing on NOx. If that is the case, temporarily retard
> your timing by 5-10 degrees. That will lower the values enough
> to get you through.
>
> Could you please post emissions results when you do this? I'd
> like to know what the reduction actually is. I have data for
> another vehicle, but not for a WBX.
>
>
> tabe johnson / 87 westy
>
>
>
> --
> mordo
> 1990 Carat
|