02 sensor voltage

[dwjohnson]

 Can someone explain the frt and rear 02 voltage reading to me, from a Power Vision. In simple terms please. In open loop, is this reading the exiting mixture ratio or what the ecm is calling for? or am I way off completely. I have noted from as low as .6 (at idle and when shifting) with 1.1-1.2  most all of the other times, with 1.7 under throttle and load. Thanks.

[Pirsch Fire Wagon]

The ECM uses a 5 volt regulator for multiple purposes (communication and sensor inputs to name a few). In this case, the Sensor begins to be heated and therefore there is the resistance is greater. As the temperature increases the resistance in the sensor changes as well which is why you see different voltage indications.

The ECM uses these variances to determine (amongst other things) how much fuel is required for a single event (detonation). And, that's what happens as the voltage changes.

[Coyote]

Can someone explain the frt and rear 02 voltage reading to me, from a Power Vision. In simple terms please. In open loop, is this reading the exiting mixture ratio or what the ecm is calling for? or am I way off completely. I have noted from as low as .6 (at idle and when shifting) with 1.1-1.2  most all of the other times, with 1.7 under throttle and load. Thanks.

The O2 voltage will switch from a higher voltage to a lower voltage around the set point. So it is normal to see it switch from around 600mV to 1800 mV. The duty cycle of the switching will vary some based on your AFR setting at that spot. The ECM drives this.

Added, this is true while the bike is in closed loop. If you go WOT and the bike goes open loop and likely richer, the sensor voltage will rail and not be switching during this time.