Eckie:

If this plug comes from the right side of the bellhousing (not firewall)
then I'd guess this is the top dead center sensor, which was to be used
by VW techs with some specialized test equipment.  Seems like some vans
from this era had it and some didn't.

On Fri, 22 Jan 1999, Eckie Prater wrote:

> I had the engine top compartment open and was cleaning, checking
> everything and I found a wire with a plug end that was not hooked to
> anything.
>
> It appeared to not have been plugged into anything in the recent past.
> The wire is gray (which matches some oe the other factory wires in the
> engine bay) and comes from the forward firewall.  It has three wires to
> the plug.  The plug is a cone shape rubber boot about 1 inch and a half
> in length and about 1/2 inch in diameter.  Recessed in the plug end of
> the boot are three metal prongs arranged in a triangle design. The wire
> length limits this to reach the fuel injection throttle area and the
> distributor area.  On the end of the boot looks like a small retainer
> clip.
>
> I am wondering;
> 1.  Where and what does this plug into?
> 2.  Is this for an electronic ignition option which I do not have?
> 3.  Is this for an instrument guage option which I do not have?
>

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