Z32 O2 Sensor trigger voltages

[Torque]

While looking at the O2 trigger voltages for Z32 I found that the values for LHS and RHS are quite different.
LHS values makes sense to me, but RHS looks funny.


Since on RB25 (type 2) we feed one O2 sensor signal into the two O2 inputs of the Z32 I'm wondering what impact that might have?

Z32O2.JPG

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[Matt]

Strange that your values are 580,580 since mine with that file show 530 (0xFFA0),580 (0xFFA1)

Anyway I've had a look at the Z32 LH02 and RH02 code today

Both LH and RH O2 inputs are compared:

Against 0xFF92 (LH02 high) and then 0xFFA0 (low) but also FFA1 (high) in one part of code
Against 0xFF92 (LHo2 high) and then 0xFF93 (LH02 low) and used to adjust rich/lean counter (used for STFT)
Against FFA0 (low) and FFA1 (high) again and the O2 voltage difference is calculated

So currently the assumed 'RHS' parameters are labelled incorrectly. It appears they are used to assist with the O2 feedback trimming (around the mid point of where the O2 sensor changes from rich to lean)

I will need to remove the 'LHS' and 'RHS' labelling since all parameters are used the same both both banks of O2 sensor (and calculated separate trims). Effectively the RHS becomes a second set of O2 voltage parameters.

I would just use the current LHS ones for the R33 adjustment. With the RHS rich, make same as your R33 rich. With the RHS lean I would just leave as is

[Torque]

Hi Matt,

Thanks for that.

My values for

O2_VOLTAGE_RHS_LOW,&H7FA0
O2_VOLTAGE_RHS_HIGH,&H7FA1

are 530 (LOW) and 580 (HIGH), so in line with your side of the pond


I would have thought that the O2 sensing window is the same both sides (just as you said)

Cheers

[Matt]

Yes that was an incorrect assumption, but looking through LH O2 and RH O2 shows both sides use the same parameters