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Subject:Re: Emissions failures make me feel like a failure
From:Richard A Jones
Date:Wed, 5 Dec 2007 21:41:17 -0700

Mordo wrote:
>         HC
>CO    NOx
>standard    2.40 GPM    80.00 GPM   3.00 GPM
>mine      0.4208 GPM  5.8560 GPM  3.1568 GPM

Tabe wrote:
> Your chart came out kinda funky on my screen, but it looks like
> you're failing on NOx.

If Tabe is right, yes, you are failing NOx, but also
are way under for HC and CO.  Either your combustion temps
are way too high (getting high NOx) or you have a leak
in your exhaust before the cat.  Your numbers look like
you are way too lean--which could give you high combustion
temps.

So check your exhaust system carefully for leaks, and
sniff at your test port before the cat to see what is
coming out of your engine.

BTW--nowhere on the Maryland web sites do they state the
limits of emissions required.  Strange...or maybe not.

Anyway, here in Colorado, the Vanagon falls under "light
truck" limits and for my '87 are
4.0 HC, 30.0 CO and 9.0 NOx.  My 130,000 mile, well-tuned
Syncro passes with
2.13, 20.91 and 5.79.  Not to brag, but to compare.  If
your "standard" numbers are correct, I wouldn't pass in
Maryland either.  But why does Colorado have 30 CO and
Maryland 80?  Something doesn't make sense to me.

(We are at 5,000' and so maybe limits are different for
that reason.)

Compare with yours of
0.42, 5.86, and 3.16 and you see why I say "too lean."

Richard