O2-sensor on carb (sorry) engine - Slant 6

[tom cloud]

>>      What is the actual electrical output from an O2-sensor (mV, mA, ohm)?
>>      I would like to connect it to a meter placed at the instrument panel;
>>      giving me the best possibility to adjust the carb.
>The output ranges from 0V to 2.0V or so.
>A good plan is to purchase CyberDyne's A/F gauge, its the type with 10
>LEDS

Go back and look at the past threads re the various EGO gauges ...
I think you'd be better served with a simple voltage gauge (it's
far more accurate and you can 'adaptively learn').  The output of
the EGO is not accurate off stoich (actually, it is accurate, it
just takes some compensation) and you're gonna want to know the
actual voltage levels -- as you're gonna want to do some tuning off
stoich.  If you'll do a web search, you can find SAE papers and other
references to EGO sensors.  I know of none that have usable outputs
over 1 volt or so.  Typical 2 or 3-wire sensors are available from
your part$ house for no more than $30 or so.

The advantages of the commercial EGO gauges:
 .. they cost more than buying the parts & doing it yourself (negative
advantage)
 .. they're nicely packaged
 .. the circuitry is already figured out -- easy to implement
 .. they're not accurate (negative advantage)
 .. they don't read out in actual a:f ratio (they can't), only give
    approximate stoich and then relative readings above and below it.
    this is not very useful for tuning, as (noted before) the output
    of the sensor (off-stoich) changes with temp and you really need to
    be able to see the actual numbers to make a judgement call about
    what it means (hence your 'adaptive learning') .... (negative advantage)


Tom Cloud <cloud at peaches.ph.utexas.edu>