That device is called an idle speed boost valve.  On 85's you will
have one for power steering and possibly one for A/C (if equipped).

Their job is to increase idle speed when power steering is turned
hard right or hard left or A/C compressor is engaged.  They don't
really do anything when driving at normal speeds, just for idling.

If it is a brown wire it should be connected to ground.  Brown is
generally ground in VW land.

>Can anyone please give me the name and functional description of the
>engine part.......and associated wire
>in this photo..........circled in yellow in the photo at the below
>webpage link:
>
>*_http://www.esnips.com/doc/0111307c-eade-4224-8d85-c454837d7216/wire1c_*
>
>
>Comment:
>
>A friend is fixing up my van  after lengthy storage period, and has
>limited experience with vanagons.
>
>*_He wants to know what this loose wire, circled in yellow, should
>connect to, and where? What is its purpose? _*
>
>He said that he touched it to something and it seemed to alter the
>engine rpms......
>
>Thank you in advance for your help and advice!
>
>James/California