O2 sensor wiring?

You need a connector view of the sensor, for most 4-wire universal oxygen sensors with:

2 white wires = heater circuit wires
Black wire = sensor signal wire
Gray wire = sensor ground/reference wire

Fat red = likely O2 heater power
Fat white with black stripe = likely O2 heater ground
Skinny green/red = likely O2 signal or signal return
Skinny red/green = likely O2 signal or signal return

Check out the images (below). Let us know if you need anything else.