3000GT AWD V6-2972cc 3.0L DOHC Turbo (1991)
Oxygen Sensor: Description and Operation
Oxygen Sensor Circuit
The oxygen (O2) sensors, mounted after the turbo chargers in the exhaust header pipes, monitor the amount of oxygen in the exhaust gas.
Oxygen Sensor (Heated)
The sensors have a closed tube made of ceramic zirconia. The inner surface of the tubes are exposed to atmosphere while the outer surface is exposed to
the exhaust gas. The differences in oxygen content makes the sensors generate an electrical current. To enhance the generating capacity of the zirconia,
the tubes are coated with platinum. The sensors are equipped with heating elements. The heating element is powered by the control relay, and reduce the
sensor warm-up time, thus improving cold engine emissions and driveablity.