I had what sounds like the same problem.  It turned out to be the idle
stabilizer unit, which is very easy to replace.  Local part stores want
around 200.00 for them,  but you can get one for far less from The Bus
Depot.

http://www.busdepot.com

Dane Tessler
87 Westfalia 138K
Treasure Island, FL
http://members.aol.com/Dane714/westfalia.html
-----Original Message-----
From: Bruce Ralphs <bar@ISLANDNET.COM>
To: Vanagon@VANAGON.COM <Vanagon@VANAGON.COM>
Date: Thursday, May 07, 1998 1:58 AM
Subject: Surging

>Hi Gang,
>
>I've got a surging problem that's developed in the last couple of days
>with my '85 Westy.  Just at idle and only when warm it will surge,
>actually more appropriately drop rpm and stall.  Not a real problem
>accept that it's always when you're coming to a stop or stopped and it
>sounds and looks like the motor is ripping out of it mounts. It's an
>automatic.
>
>A mechanic has started initial investigation and is looking at replacing
>the air flow sensor to a tune of about $500 Canadian!  This is alot more
>than I was hoping it would be, you know, bad gas, faulty timing,
>disconnected hose, etc...all of which are around $50!!!
>
>Any experience with this, anyone?
>
>I haven't been on the list for a couple years, it's good to be back.
>TIA, Bruce
>
>
>----------------------------------------------------------
>
>Bruce Ralphs                               '85 Westy, 141K
>250-727-7617                               '91 Passat, 95K
>250-727-7685 fax                           '83 GTI,  256K