I often find the throttle switch not making contact at idle..
and the timing too advanced.
and you want it running as warmly as you can get it for the test..
like don't shut if off waiting for the test,
and make sure it's running fully up to temp.

if the fuel is old, fresh fuel couldn't hurt.
there is the CO adjusting screw on the AFM but normally that's not messed
with.
and oxygen sensor ...
make sure that's working like it should.
And hopefully your cat is good ..
and ignition parts are quite strong on these...but if those are flakey or
old or non-bosch ...
might consider that too.  No exhaust leaks of course.
On rare occasions I have found injectors that leak.
Scott
www.turbovans.coms
----- Original Message -----
From: "Todd.Last" <Rubatoguy@COMCAST.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, December 30, 2010 7:48 PM
Subject: Failed emissions testing

>I went to have my Westy emission tested today, and it failed the test.
> The van had been sitting for a number of months, and when I first
> started it, It sounded like one lifter was devoid of oil. I let it run
> for awhile and the noise went away.
> I'm not sure, but it looked like the oil was a bit overfilled as well.
> Anyway my numbers were (at idle)
>
> 270 HC  (Max allowed is 220)
> 1.43 CO (Max allowed 1)
>
> Any suggestions on what to adjust to try again?
>
> thanks,
> Todd
> '88 Westy