Hello

I need to know the color of the wires going to the front and rear O2 sensor I have done the Eco swap on my 98 coupe and have both female connectors from the PCM close to each other so I need to know witch one plugs into witch plug thanks again!!

Hi AJ,

This is for an '05 Cavalier, my guess is that it is the same for your car as well.
Sensor 1 is in the exhaust manifold. Tan is signal low, purple is signal high, dark green is heater low control, pink is heater ignition voltage.
Sensor 2 is post catalytic converter. Tan/white is signal low, purple/white is signal high, black/white is heater low control, brawn is heater ignition voltage.

Heater is switched (control) at the ground level, the other end of the heater is at +12V (ignition voltage).

Good luck, Peter

No such thing as sig high and sig low...

The polarity of the ox-sensor indeed does matter, it outputs a DC (direct current) voltage.
The ox-sensor is in essence a "high temperature battery" where the electrolyte is the exhaust gas. The output voltage of the "battery" depends on the electrolyte, on the oxygen content of the exhaust gas.

The signal names are from the factory service manual.
If you think that the naming is not appropriate, take it up with GM.

Peter