High CO along with high NOx points to both a bad O2 sensor and catalyst. A
number of states including New York are adopting the California standards
which include no after-market catalysts  because those just don't work as
well or for as long as they need to. There are CARB approved units available
for the Vanagon. A non-working O2 sensor will help to ruin the Catalyst. So
too will any miss-fire situation, coolant into the engine, certain sealants
used on gaskets, bad injectors, etc.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
David M
Sent: Saturday, June 15, 2013 3:43 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Emissioins test failure

My 1987 Vanagon failed its Arizona emission test this morning. Results were
Hydrocarbons (HO) grams/mile .75 limit 1.60 (passed), CO grams/mile 25.73
limit 15 (failed), NOX grams/mile 2.91 limit 2.5 (failed).
I have the standard printed list of what might cause these results. The last
time it failed 2 years ago, it failed only the NOX reading and I had to get
a new catalytic converter that cost over $500 I've noticed the low-speed
engine fan comes on a lot more than it used to and sometimes it even goes to
high-speed which is a scary thing because it makes the entire vehicle
vibrate and I can feel it through the gas pedal.
According to the testing station you can request a second-by-second graph of
the emissions test but they will only fax it to a repair shop.