The O2 sensor light is NOT powered by the the O2 sensor.  There is a mileage
counter box (called a "time box" by some,) between the upper and lower
speedometer cable that "trips" the light on a certain mileage levels (30K,
50K, don't really remember).  To reset and turn off the O2 sensor light, you
gotta crawl under the left side of the van, trace the lower speedo cable to
the box, find the hidden button, press it firmly and the light goes off.
It's set up this way to remind the owner to check the sensor when it comes
on, to see if it needs replacing (I replace mine every 50-60K myself).

Now OTOH, your sensor and it's connection may be bad, causing the rich
condition in the first place.
YMMV
--
Jim Thompson
84 GL 1.9 "Gloria"
84 Westfalia 2.1 "Ole Putt"
73 K Ghia Coupe "Denise"
72 411 Station Wagon "Pug"
oldvolkshome@gmail.com
http://www.oldvolkshome.com
***********************************
On 5/24/07, C B <cunegonde.van.westfalia@gmail.com> wrote:
>
> b) Post overheat, my O2 sensor light is on and the engine is running
> very rich (judging by smell). The PO somehow damaged the O2
> sensor-to-green wire connector so almost all the wires are broken on
> the harness side if the connector. Do I connect the black wire to the
> wires running free inside the green wire in the harness, or to the
> inner green wire inside the same green insulation? Bentley offers no
> clues. I believe the O2 sensor is a "generic" Bosch.
>
>
> --
> Bretts
>
> 1983 1.9l WBX Ivory Westfalia "Cunegonde"