Backward 02 sensor?

[Tom Parker]

Hi,

I built an EGO sensor gauge using a Jaycar kit based around the LM3914.

I got my sensor off a Mitubishi 3 litre v6 car. I don't know what model, as
the badges were missing in the bone yard.

The gauge works as expected.

The sensor does not. It seems to be backwards. As I understand it, low
voltages point to a lean condition and high voltages point to rich. On the
car, my guage reads about 0.85v cruise and flashes to around 0.1v when you hit
the throttle. I'm running it in an out of tune mini, which is running rather
lean at the moment.

When I pull the choke out, the voltage drops to around 0.1v.

The sensor seems to respond very quickly, and does everything that I expected
from reading here, except that the voltages seem to be reversed.

I had it in a flame from a butane torch, and it would read very low voltages
while inside the flame, and would read 0.85v while in the air or in the 
flame exhaust. On occasion the voltage went negative, to about -0.1v.

Is this normal? Anything to worry about?

The sensor is a 4 wire unit, and I couldn't find any manufacturer's name,
although there is something undneith some underseal on it.


--
Tom Parker - parkert at ihug.co.nz
           - http://www.geocities.com/MotorCity/Track/8381/