Anyone have a wiring diagram for a \'91? I'm trying to figure out which wire is the signal from the O2 sensor so that I can get my air/fuel gauge installed... The wire from the O2 sensor is gray, and tracing the wire as far as I can it goes into a larger loom, but I cant trace it part of the way because it goes inbetween the firewall and back of the motor. The part of the loom I can get to does have 1 grey wire in it, but I'm not for sure that this is the same wire. If anyone knows what color the wire should be, that runs back to the computer, please let me know. Thanks.