Hey Volks.

Yup, black wire is the signal wire.

At the risk of getting people's undies in a bunch, What I would do is
get a 4 wire sensor. You can get a genuine Bosch from Kragen or
whatever your local big chain is for about $60 - $70. Try Part #13275
or 15704. Believe it or not, this are listings for a Chrysler and
Dodge/Jeep. What the fourth wire gets you is a ground wire. So, instead
of relying on the thing grounding through your exhaust system as the
current one does, you can run the ground wire to a good grounding point.

Of course, you'll have to splice on the connector for the heater wires
and crimp on a new spade for the signal wire.

This is what I would do...YMMV

Eric Fournier
91 GL
On Saturday, April 26, 2003, at 10:36  AM, Brian Doss wrote:

> A couple of questions on the 3 wire sensor. ('88 2.1 L).  If I
> understand
> this thing, the two white wires are to heat the O2 sensor, and the
> polarity
> is not important... Right? Now, that leaves the black wire to be
> connected to
> the fat green wire. Is that the signal wire, or is it a ground wire??
> Secondly, does the wire have to be sheilded?
>
> Thanks - Brian Doss
>