Date:         Thu, 21 Jun 2007 12:20:30 -0700
Reply-To:     Old Volks Home <oldvolkshome@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Old Volks Home <oldvolkshome@GMAIL.COM>
Subject:      Re: Aux Air Valve becoming available as reman
In-Reply-To:  <002501c7b407$558ca580$0302a8c0@m848axp3200tom>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

What Tom describes is exactly the same for the 83.5-85 Wasserboxer.  The Aux
Air Valve was dropped when the 86 2.1 models were introduced.  The Aux Air
Valve introduces more air into the plenum because the ECU during warmup is
sending signals for a richer fuel pulsation at the injectors.  The extra
air compensates for this.  When the ECU switches to a leaner mixture (about
2 to 3 minutes), also known as "closed loop" for the O2 sensor, the Aux Air
Valve's Bi-Metal strip has been heated to the point where the valve opening
has closed, shutting off air flow to the plenum - sort of a "choke" in
reverse.  So simple, that only a child would know this, right ;-)

Geza - The Bentley Manual is for those mechanics at the dealer (at the time)
who received additional & specialized training for each particular model of
VW being produced or introduced.  When I first came upon the Vanagon Bentley
the first time, I was totally lost because I was used to the literal
step-by-step Bentleys of the earlier models (like the Bay Window).  In fact
if it wasn't for my personal experience wrenching on L-Jet FI on the Bay
Window and it's Bentley Book, I would have been totally lost.  Knowing what
and how certain L-Jet (which is what Digijet really is) compenents really
helped in getting to know the Vanagon Bentley.  They're not for beginners,
that's for sure. ;-)
--
Jim Thompson
84 GL 1.9 "Gloria"
84 Westfalia 2.1 "Ole Putt"
73 K Ghia Coupe "Denise"
72 411 Station Wagon "Pug"
oldvolkshome@gmail.com
http://www.oldvolkshome.com
***********************************
On 6/21/07, Tom Young <tomyoung1@comcast.net> wrote:
>
> From: "Geza Polony" <gezapolony@SBCGLOBAL.NET>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Wednesday, June 20, 2007 8:48 PM
> Subject: Re: Aux Air Valve becoming available as reman
>
>
> > But the aux air entry into the throttle body is before the butterfly
> > valve.
> > Wouldn't the butterfly valve control the air flow no matter what you
> > inject
> > on the other side?
>
> Humm... I'm talking about the aux air regulator that exists on air-cooled
> Vanagons.  This "plumbing" for this regulator is as follows: hose from "S"
> boot allows metered air to pass to the aux air regulator which then allows
> this air to pass into the air distribution box which is *after* the
> throttle
> body.  There's no entry point for air from the aux air regulator into the
> throttle body itself.
>
> When the aux air regulator is open there's another pathway for metered air
> to enter the engine.  When the aux air regulator is closed then the
> position
> of the butterfly valve alone controls how much air is allowed into the
> engine.
>
> Tom Young