Well I am going to have to call you out on this one. There is no input for an o2 reading on the SAFC2. I have been looking over mine and saw that you have connections to the rpm signal, throttle signal, knock signal, air input signal, air output signal, two grounds, and one hot wire. So if you can tell me how the o2 reading in the SAFC2 is getting a signal and how you can read it, I will then be amazed. (No slam is intended here.)

 

There is an alternate input wire, Its not a true O2 gauge, but the sensor input wire for the other sensor that is unused on the S-AFC configured for MAF (Karmann)

The problem is there is no direct "Gauge" for it, but there's a mode called Sensor check, whic displays the Sensor voltages for TPS, MAF, and VPS (Vane Pressure Sensor) so if its hooked up, it will register a voltage on that screen...

Its not a true built in feature, but something we had discovered early on that can be done.

Again, like I said before, don't rely on a Narrowband sensor (factory O2 sensor) for being able to adequately tune safety, but it will be able to tell you when the settings are horribly off and lean enough to be dangerous.