I was installing my air/fuel ratio guage today, and I can't really figure out which wire is the signal wire from my o2 sensor. There is four wires there and I am not sure which wire is the one that goes to the PCM (Powertrain Control Module)....
If anybody has any info on this plz let me know.

 

if there is only 4, is there harm if u try them all. This is just a stupid suggestion cause i do not know if you can mess something up.

 

if you have a heated o2 (4wire o2) then you have 2 grounds, a signal and a power wire. I would use a multi-meter and probe the 2 non-ground wires (should be the same color). have someone rev the car up will probing each of the leads...which ever one varies the voltage (0-5v iirc) that's your signal wire.

 

There is 2white(ground), 1grey(heated), and 1black(signal) before the bracket or a converter. After the converter, there is 4 different wires with all different colors. I tried connecting it to the black(signal) wire, and one of the wires on the same spot, but the opposite side of the black(signal) wire(its white with something). When I probed it, it kept getting crazy signals going up and down and not really working correctly... Any suggestions?

 

PS. good luck with the SouthEast Meet in Alabama, sorry cant be there Roddimus Prime