I finally solved this problem!  First,  I cleaned up the throttle linkage
and body as recommended by Mark McCulley,  and then I had the sensor next to
the thermostat tested (it was within spec), as suggested by Joel Walker.
I'm glad I did those things for the sake of maintenance,  but they did not
do the trick.

My mechanic has an 86 Vanagon.  I asked him to swap out his Idle Stabilizer
unit with mine to see what happens.  That did it.  It ran perfectly at all
temperature ranges.  Idled solidly at 950rpm in gear, about 1150rpm in
neutral...no high idles or "hunting".

I priced out a new stabilizer unit...new: 190.00,  local junkyard: 75.00.
I popped in the one from the junkyard (no tools necessary) and again,  the
problem was gone.

FYI,  the part # for the idle stabilizer unit is:  035 133 455F
If anyone is looking for a used one,  there is one more available (at this
writing) at Allum's European Automotive in St. Petersburg, FL.
Phone:  800 282 1829  (local:  813 321 6221).

Thanks Mark and Joel for helping me with the process of elimination!
-----Original Message-----
From: Dana Tessler <dane714@WORLDNET.ATT.NET>
To: Vanagon@VANAGON.COM <Vanagon@VANAGON.COM>
Date: Wednesday, March 18, 1998 10:07 AM
Subject: Re: "Hunting Idle"

>I have a 1987 Vanagon GL Camper.
>There is an electronic sensor hookup at the throttle linkage on the engine.
>I had a problem with the van idling at high rpm until I tickled the gas
>pedal,  then it would go back down.  A real pain in the butt in town.  My
>local VW mechanic said it was a faulty sensor and recommended disconnecting
>it, which I did.  Now,  the idle problem is gone,  but unless the van is
>really warmed up,  it will stall out when I come to a light.  It even does
>this occasionally when the van is completly warmed up,  but rarely.
>
>Any comments appreciated
>