I guess that's it. It's not actually part of the oil breather, but it's mounted horizontally on a bracket that shares one of the oil breather base screws.
It has three prongs inside a rubber boot. Wasn't able to trace to the other end, got lost among other wires.

I was able get a decent photo of it, but I don't have a photo-sharing account set up to allow me to send it to GERRY.

Thanks, Steve

--------------------------------------------
On Thu, 12/4/14, Neil N <musomuso@gmail.com> wrote:

 Subject: Re: Missing Female at Oil Breather Base
 To: "Stephen Engel" <sengel543@yahoo.com>
 Cc: vanagon@gerry.vanagon.com
 Date: Thursday, December 4, 2014, 2:13 PM

 Is the other end of the
 plug at or near the flywheel area on passenger
 side? If so, it's likely an OEM sensor VW
 used with one of their VWxxx
 diagnostic
 machines. IIRC, this sensor is used to determine TDC or
 RPM
 for certain tests.

 pic of TDC sensor on my '88 Westy:

 http://tinyurl.com/pfm7jkq

 Neil.

 On
 12/3/14, Stephen Engel <sengel543@yahoo.com>
 wrote:

 > There's a
 male plug at the base of the oil breather on my 87 Syncro
 2.1 WBX.
 > Is there a missing female
 plug/sensor?

 --
 Neil n

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