Heated Oxygen (O2) Sensor

The oxygen sensor is located on the exhaust manifold, near the exhaust pipe flange. The oxygen sensor provides an input voltage to the ECU relating to the oxygen content of the exhaust gas. The ECU uses this information to vary the air-fuel ratio. The oxygen sensor is equipped with a heating element that keeps the sensor at proper operating temperature during all operating modes. Maintaining correct sensor temperature at all times allows the system to enter into closed loop operation sooner and to remain in closed loop operation during periods of extended idle. Voltage to oxygen sensor heater is supplied through the oxygen sensor heater relay.