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Old 05-19-2022, 05:35 PM   #3 (permalink)
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Originally Posted by Piotrsko View Post
Might be wrong here, but I was understanding that it was a frequency and not a voltage since the data input was digital on or off only. The resistor would cause the leading edge to peak sooner and decrease off frequency and if it was actually a sine wave, tend to increase the waveform towards clamping which would be the same result.

If the off frquency goes below a target value it means one state probably rich, if it goes above it's lean. Easey peasey to do digitally.
I think you might be referring to the catalyst monitor function. Typically wideband cars also use the rear narrowband to calibrate the wideband (since the wideband has no fixed stoich reference, as the measured current at stoich can drift over time). I had this experience attempting to force my Scion FR-S into lean burn, where the car started recalibrating the wideband O2 on the freeway.

Bumping the voltage up will move the switching point just a little bit to the lean side. On some cars that run VERY rich, you could probably increase heavy acceleration efficiency by over 2.5% doing this, which is pretty significant.
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