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O2 Sensors...MORE....

A comment was made that it is not wise to use nothing other than a DMM to
seek voltage at the O2 sensor. This is not entirely true. non digital
multi-meters will not fry or otherwise impair standard O2 sensors, according
the instructor I had when I went to school at Bosch. As a matter of fact,
they are actually preffered over DMM as you can see the swing in voltages
much better. After all, the typical O2 sensor is putting out simple analog

On the other hand, the latest and greatest sensors are no longer analog.
Toyota came up with the worlds first digital O2 sensor designed to make much
faster computations than the slower, now older units. 

One neat little trick you can do if you lack any type of volt meter is to
touch the O2 sensor output lead (if it's the type with a sep. wire and
connector) and with your other finger touch the positive or negative side of
you battery. Touching the pos. side will fool the computer into thinking the
car is running rich, therefore leaning the mixture out. Touching the neg.
side will produce the opposite effect. Not all people are that good of a
conductor to make this work. This is a quick test to see if the entire O2
sensor circuit is functioning. 

The only way I know of in order to fry an O2 sensor is to slam 12 volts into
it, or feed allot of lead into the gas tank. One must also be careful not to
smear anti-sieze compound around the openings of the sensor itself. 
                       Rolf Mair is: waves@epix.net
        Racing Resume for Sponsors/Corvettes for sale/Racing Pix @
    Head Coach and Founder of the Seventh Wave jr. Ski Racing Team @ Doe Mt.Pa
               1994,95,96 East Coast USA SCCA Solo 1 Champion