This sounds like the rarely-seen Top Dead Center (TDC) sensor that some
of the Type IV motors came equiped with.  It's supposed to be used by VW
techs in diagnostic procedures.  Look in the wiring diagrams in your
Bentley and you'll find it as a little "stand alone" piece.

On Mon, 19 Jul 1999, Mark Kazman wrote:

> I have an 81' air cooled vanagon with a suspicious wire that Ii can't
> seem to find out where it goes. The wire is coming out of the engine
> case on top, right near where the engine bolts to the transmission.
> At the other end of the cable is a connector which looks like the ones
> on the idle speed  stabilizer. I searched through the bentley and saw a
> photo of the wire coiled up, but no reference as to where it goes or
> what its used for. Anyone have any ideas what this is and where it goes?

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Tom Young               young@sherlock.SIMS.Berkeley.EDU
Lafayette, CA  94549    '81 Vanagon
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