you need 2 wires. trust me.
i've got the schematics for one at home if you don't mind waiting until the end of the day.
i think it's 1 microfarad capacitor and 1 megaohm resistor and 2 wires. let me see if i can draw it here from memory
-----|----/\/\/\-------white wire
cap> _
cap> |
-----|-----------------black wire
the /\/\/\ is the resistor and _ is the capacitor, and the o2 sensor would be on the right side of the wiring, splicing in between the sensor and the harness.
don't quote me on any of that...
i'd definitely wait til i got home so i can at least double-check it, but i'm pretty sure that's right.