Thanks Mark,

I hadn't realized that wire was coax; the outer shield was twisted
around so that it looked like a heavier gauge wire and I couldn't tell
there was a center wire there.

That should help immensely.

Happy Trails,

Greg Potts
1973/74/79 Westfakia "Bob the Tomato"
1987 Wolfsburg Weekender Hardtop
www.busesofthecorn.com
www.pottsfamily.ca

mark drillock wrote:
> The white/green is not it. The white/green is there to connect the A/C
> compressor clutch signal to the idle control unit so it knows when to
> speed up the idle for the A/C.
>
> The thick and stiff green wire is the one for the O2 sensor. It is coax
> so great care must be taken with it. The center wire inside must not
> touch the braided shield wire that is layered around it inside the outer
> insulation.
>
> Mark
>
> Greg Potts wrote:
>> Hi Volks,
>>
>> One of my projects today was to install a new O2 sensor on my van and
>> hook it up to one of Ken Lewis' sensor feedback widgets.
>>
>> Step 1: Fish the wire through from the engine bay and install the sensor
>> in the dash with power. DONE.
>>
>> Step 2. Hook it up to the wiring harness at the sensor, to test the old
>> sensor before removing it.  DONE.
>>
>> Step 3. Power up the sensor gadget and see what happens. It reads fully
>> rich, indicating there is no power coming from the sensor. OK; I kinda
>> figured the sensor was dead to begin with anyway.
>>
>> I swapped in my new sensor; same result, even after warming the engine
>> for several minutes.
>>
>> So I checked the heater wires to the sensor, and discovered it isn't
>> getting power. Chasing the leads upstream, the original wiring harness
>> has been hacked. Under the electrical tape covering the splices it looks
>> like none of the wires were actually connected. Alongside the wires
>> leading to the 3/4 injectors I have 4 wires available to work with;
>> white, brown, white/green and a thicker gauge green wire.
>>
>> My vanagon is an 87 running original digifant FI and 2.1 cooling system
>> on a 1.9L block.
>>
>> My Bentley tells me the white and brown supply power to the O2 sensor.
>> No Problem there.
>>
>> But Bentley DOESN'T tell me what wire goes to the O2 sensor. From the
>> mess I pulled apart, it initially looked like the thick green wire was
>> the right one to use. That doesn't seem to work; it kills all the lights
>> on the sensor feedback device and the engine idles very poorly.
>>
>> Running the white/green wire seems to work better, but after a few
>> moments the idle drops and the widget goes back to reading low voltage.
>>
>> If someone can help me find the right wire to connect to the feed from
>> the O2 sensor I'd really appreciate it.
>>
>>
>> Happy Trails,
>>
>> Greg Potts
>> 1973/74/79 Westfakia "Bob the Tomato"
>> 1987 Wolfsburg Weekender Hardtop
>> www.busesofthecorn.com
>> www.pottsfamily.ca
>>
>