2002 Blazer Help O2 Sensor

[hhosurfer]

I have been working on this for some time and just can not figure this out. It seems the ecu sends a test voltage on the blue wire to the o2 at startup. Most o2 sensors use the blue wire for the sensor signal. But from what I see the voltage on the blue runs 1v to .01volts (normal) but the white also fluctuates the same as the blue.

I added a EFIE device gas went down. Put Resistor on blue wire gas goes down, 15k resistor from white wire to ground gas mileage went up a little. or so it seems.

This does not make sense. So for this drawing what can you tell me about this o2 sensor?

Although the blue and white wires are on the o2 sensor, these colors are for the wiring harness.

Thanks for your help