Oxygen Sensor

[KEEPINGITREEL]

What is the code? Most O2 sensors also have a heater inside them, so that it takes less time to go into closed loop operation(ECM/PCM controls injector pulsewidth to reach proper air/fuel mix, instead of running on a preprogrammed parameter.) If you haven't noticed a drastic change in fuel economy, than I prob wouldn't replace it yet. Just becasue the heater dosen't work, dosen't mean the O2 side isn't functioning.