I'm surprised someone hasn't made a convertor to change the 0-5V signal to a 0-1V signal that the ECM could read. Think it could be as simple as a resistor?
The problem is, the NBO2 is primarily just a switch. When your exhaust goes above Stoich (>.450V) the ECM thinks your AFR is rich and tries to lean out the mixture, and visa versa. With the WBO2 you're targeting Lambda, not lean/rich. 0v = 7.35, 5v = 22.39 AFR (the opposite of the NBO2 - the higher the voltage, the leaner it is) on the one I posted. So, as an example, I wanna got 16.5 AFR when driving Lean Cruise. With the WBO2, I know when it's there. With the NBO2 I'm guessing. When in Closed Loop, my cAFR will level off quicker with the WBO2 while INT/BLM can take a while before getting close.
As an example, I have my target AFR set to 14.5. On the right side, note cAFR: and WB: apposed to INT/BLM. IIRC it took about 15 minutes for INT/BLM to level off running in Closed Loop. It shouldn't take that long. Evidently my VE tables weren't dialed in yet.
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In PE (Performance Enhancement), based on TPS Position, I target 12.3 - 13.3 AFR depending on RPMs and the ECM will shoot for it immediately. Without the WBO2 you pretty much have to rely on your VE tables.
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