Heated Oxygen (O2) Sensor

The O2 sensor produces an electrical voltage in response to the amount of oxygen in the exhaust gases. The O2 sensor is mounted in the exhaust manifold and is electrically heated internally for faster switching from open loop to closed loop operation. By monitoring the amount of oxygen in the exhaust gases, the O2 sensor acts as an rich/lean switch. This is accomplished through SMEC, which reads the voltage signal from the O2 sensor and adjusts injector pulse width (on time) to maintain proper air/fuel ratio.