Hi ..
sounds like clutch chatter.
Normally a vanagon clutch is very smooth to engage,
the pedal strokes in a nice smooth, not-high-effort way, etc.

If it is oil on the clutch disc causing clutch chatter ..
there is a trick to temporarily improve it. ..

the throttle switch failing to break contact with throttle above idle
would cause you symptom..
as mentioned..
that's  very  rare IMO - I've never seen it.
about 70 % of 2.1 vanagons that I see  have their throttle switch not
making contact at idle like it should.
And one stuck in the closed/idle position would very much confuse the
ECU indeed.

vanagons have very smooth clutches ..
and very well-lasting ones too.  It's one of the 'quite good' areas of
Vanagons ..
and yet another reason why they are such wonderful machines.

Scott
www.turbovans.com

On 9/26/2012 4:23 PM, Tom Carchrae wrote:
> Google for "Vanagon Syndrome"... lots on this, although not clear if
> it fits you.
>
> That said, being a green-horned vanagon owner, I find the clutch on
> mine very particular.  It is like no other standard I've driven.  If I
> am not very careful in letting out the clutch slowly, it will shudder.
>   I compensate and I can drive it smoothly, but I wondered it if this
> is normal for the 'torquey' vanagon.
>
> I have not worried much about it because I have had two specialist VW
> shops drive it and neither mentioned this as a problem.
>
> Tom
>
>
>
> On Wed, Sep 26, 2012 at 2:01 PM, David Beierl <dbeierl@attglobal.net> wrote:
>> At 03:29 PM 9/26/2012, Alfred Bagdan wrote:
>>> Could it be anything else that could cause this jerky motion?
>>
>> If the throttle switch fails to open it will cause severe bucking at low
>> rpm.
>>
>> Yrs,
>> d