Wide Ratio O2 meter

[Tony Bryant]

> From:          garfield at pilgrimhouse.com
> To:            diy_efi at efi332.eng.ohio-state.edu
> Subject:       Re: Wide Ratio O2 meter
> Date:          Wed, 11 Mar 1998 19:01:51 -0800
> Organization:  Pilgrim House
> Reply-to:      diy_efi at efi332.eng.ohio-state.edu

> So instead of directly MEASURING the existing oxygen ion concentration
> in the exhaust gas, you feed the Nernst cell membrane being exposed to
> exhaust gas, WITH oxygen ions sufficient to achieve stoich in that
> membrane (the sensor), measure the amount of oxygen it took by how much
> current you fed to your oxygen ion pump, and voila, you know the exhaust
> gas oxygen level, indirectly, by knowing how much oxygen it took to
> raise-it-to/deplete-it-from stoich. Neat, huh?
> 

<snip great explaination>

Now here is an idea:

What about building a small sealed box around a standard passive 
sensor, and modulating the air pressure in that box?

Does less absolute pressure move the knee down to a richer mixture?

Would this work, and could the sensor stand the differential 
pressures?



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