Installing Autometer Air/Fuel gauge

[tmnismo91]

The vehicle is a '91 Maxima w/ the VG30E motor. I am trying to install my air/fuel ratio gauge and can't determine which is the hot wire on the 02 sensor harness. There are three wires (green, white, and black). When I connect to the green wire, start the car, the gauge does nothing. When connected to the white wire, start the car, the gauge goes berserk. The readout doesn't seem acurate. Also, some guys connect down by the ecu whereas I connected to the harness in the engine bay. Are there any advantages/disadvantages to this? And help me find the hot wire. Please advise.

-Sean

[maxhopper]

From what I can see on a wiring diagram, the white wire is the signal wire. Sorry I can't be of further help, but I have not personally installed one of these before.