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Subject:Re: Super high HC on smog test - help
From:Dennis Haynes
Date:Thu, 28 Jun 2007 23:41:57 -0400

HC at that level indicates major miss fire or more likely a bad valve.
Compression and leak down test is defiantly in order before tampering with
the air flow meter. Is it this bad only at idle? Over advanced ignition
timing can cause a high idle with insufficient air flow which will effect
HC and CO.

Testing in this order:
 Leak Down and compression.
 Ignition system condition, adjustments.
 Confirm all basic adjustments. Mixture screw only effects idle but if you
can change the mixture, then O2 sensor not working properly.
Fuel system pressure and injectors
Exhaust and catalytic converter.

When all of these are confirmed proper. It should pass.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike Meuser
Sent: Thursday, June 28, 2007 11:21 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Super high HC on smog test - help

Hi - Just took my 83-1/2 water cooled westy in for smog test. I'm in
Eureka, CA where smog test is only required on transfer so it's been
about 5 years since last smog.

 Amazingly the HC at idle was 6344 and the max allowed is 250 -
that's like 25 times over the limit!  At 2500 rpm it measured 1733
and the max allowed is 200 - that's overr 8 times the limit!

The engine seems to be running smooth.  You'd think that if it was
missing so badly to spit out that much unburned fuel that it would
hardly run.

Is it possible to have values this high and still have what seems to
be a good running vanagon?  Could the test be bad?  Could this be a
very bad and clogged catalytic converter?

There is no outward sign of running super  rich - no black smoke, no
heavy exhaust smell.

Anyway, wondering if new plugs, wires, rotor and cap would fix such a
terrible showing at the smog station or are there other things I
should be looking at?

My experience is that these are always difficult to smog, but not
THIS difficult :)  Any help appreciated.

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