it came from this guy on thesamba I think...
Chris Corkin 

http://www.thesamba.com/vw/classifieds/detail.php?id=514460

on the the part  it says 
Vanagonperformance.com . 

VAC2 SN :  00107 
Electronic Throttle Switch 

  ----- Original Message ----- 
  From: Ry 
  To: Scott Daniel - Turbovans 
  Cc: vanagon@gerry.vanagon.com 
  Sent: Friday, July 09, 2010 6:48 AM
  Subject: Re: engine revving at idle

  got a link for us to this pressure switch replacement for the throttle position switch?  

  -Ry
  http://www.google.com/profiles/rylincoln

  On Fri, Jul 9, 2010 at 2:23 AM, Scott Daniel - Turbovans <scottdaniel@turbovans.com> wrote:

    re

    Is it just a matter of adjusting the
    throttle valve?

    no, you adjust the throttle switch.
    On a 2.1 it can be tricky, and sometimes they're stuck in one position, and
    sometimes they're just corroded and won't move, and sometimes they'll move
    and adjust but won't reach correct adjustment.

    it takes a small allen wrench ..
    it's loosen a clamp screw, turn an excentric, down in there.

    I just discovered a device that totally transcends this mechanical switch ..
    and that is a dodgey system after years and millions of miles..
    the throttle bodies do wear, plus what I mentioned about the switch above.

    there is an electronic replacement. I'l lbe installing one by the end of
    july ..
    it's a pressure sensor that signals the ecu when idle and WOT are happening
    ..
    and it does it by sensing air pressure, NOT by mechanical position of
    something ..
    should be 300 % more accurate and consistent, at least.

    Scott
    www.turbovans.com

    ----- Original Message -----

    From: "Mark" <mbrush@GMAIL.COM>
    To: <vanagon@GERRY.VANAGON.COM>

    Sent: Thursday, July 08, 2010 6:02 PM
    Subject: Re: engine revving at idle

      Thanks for all the suggestions - not sure, but I think I found a problem
      with my throttle valve switch.  I followed the test on page 24.59 of the
      Bentley "Throttle valve switch, checking and adjusting."

      I get continuity when I start the test, at idle.  Continuity breaks when I
      open the throttle (continuity good at full throttle), but then when I do
      as
      the manual says and "close [the throttle] slowly" - I get no continuity at
      idle again.  I can only get continuity again when I open throttle and let
      it
      snap back into place.

      Seems to explain my symptoms since it says "warm engine will have NO fuel
      deceleration shut-off or DLS function at idle" if gap is too small....

      but I can't get any continuity when I "slowly" bring back into place

      So what now?  How do I fix this?  Is it just a matter of adjusting the
      throttle valve?  Why does it get continuity when it snaps back into place,
      but not when I slowly bring it back?

      On Wed, Jul 7, 2010 at 11:36 PM, Mark <mbrush@gmail.com> wrote:

        Has anyone had this problem?  After my engine reaches operating temp and
        is
        in stop and go traffic, it doesn't fall back down to idle after I
        accelerate
        to move forward in traffic.  It just stays revved at 3,000 rpm or
        thereabouts.  Not fun when stuck in traffic.  I'm thinking it has
        something
        to do with the spring on the throttle (maybe needs to be cleaned or
        greased?).   I haven't worked on this part of the van yet, so I'm not
        familiar with how the accelerator cable hooks up and works in the engine
        compartment.

        Thanks for any insights!

        Mark

        --
        Mark
        1990 Westy (2.1 - manual)

      --
      Mark
      1990 Westy (2.1 - manual)