EGO sensors

[tom cloud]

After some research, I have found a few tidbits that might be of interest.
The 'standard' EGO's output curve is sharply non-linear (like a stair step),
with the flat part occuring at stoich with about .45 volts output.  Above
and below this point, the voltage curve is very steep and its relation
to A/F does not seem to be well documented.

Well, that much I already knew (as did most everyone else).  The interesting
point is that the EGO can give useful information above and below stoich.
But, the temperature of the sensor greatly affects the sensor's response
to the A/F mixture, so it's not of much use (without knowing its temp
and having calibrations curves).