How did you discover your vacuum leak?

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM]On Behalf
Of Larry Alofs
Sent: Friday, March 16, 2001 7:02 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: CO adjustment

Todd Last wrote:

> I replaced my AFM and now need to adjust the CO. Is this something that
> a garage mechanic can do, or is this something that I need to take the
> van to a shop for.
>
> I guess there is no such animal as a cheap CO sniffer.
>
> Todd
> '88 Westy

Very interesting question.  Considered it myself a few years ago when my 84
failed the Illinois smog test.  I wanted something that would at least tell
me whether things were getting better or worse when I tried various
adjustments.
  I bought a home type CO monitor with a digital display for about $30 or
$40.  Unfortunately it took two minutes to take each each reading.  It was
also designed for much lower CO levels than you find in exhaust so I had to
try to find a way to dilute the exhaust by a reproducible amount.  I spent
way too much time fooling around with aquarium pumps, hoses, bleeder and
mixer valves etc. without much success.  Eventually I discovered a big
vacuum leak in the intake area and after I fixed it the O2 sensor voltage
started to act sensibly.  Passed the smog easily and abandoned the sniffer
project.  C'est la vie.

Larry A.