electrical bonding with light gauge wire between the engine or chasis to
the body of a one wire O2 sensor is not necessary, and is generally not
good practice because it becomes a possible fire hazard if the engine-
chasis bonding strap fails. further, the O2 circuit is high impedance, and
the output therefore isn't sensitive to small contact resistances and so
on - although cleaning the threads on the exaust pipe with a tap and using
plenty of copper anti-seize compound is a good idea.

the real test is to measure the voltage between the body of the O2 snesor
and the engine -  and also between the engine and chasis. more than 10 mV
or so would be worth investigating, and the greater the electrical load
(lights etc.) the more snesitive is the test.

On Sat, 25 Mar 2006 06:56:46 -0800, Evan Mac Donald
<macdonald1987@SBCGLOBAL.NET> wrote:

>Any body got any other ideas for attaching a seperate ground to a 1-wire
O2 sensor? I don't want to trust the rusting exhaust system and its
connections. The only permanent connection I can think of is to solder a
lead to the outer housing, but I am afraid that even the upper edges get
too hot, and will remelt the solder. Can a lead be welded on? How much
heat is too much? I can braze a connection in place, if that won't destroy
my shiny new sensor.
>
>  And that raises another question. On a newer-style, self-heated O2
sensor, is the ground only for the heating element, or does the sensor
also use that same ground?
>  In other words, does the sensor ground through the housing and then the
exhaust system, or does it also use the ground for the heater?