Oxygen Sensor: Description and Operation

Oxygen Sensor (Typical):

The oxygen sensor is an exhaust mounted measuring device for determining the oxygen content in the exhaust gases. Since the amount of oxygen in the exhaust indicates precisely how complete the combustion of the air/fuel mixture in the cylinders is, it is also a good place to determine the air-fuel ratio. The oxygen sensor senses oxygen (O2) content in the exhaust and converts it into an oscillating voltage signal that is processed by the ECU. The OS inputs the ECU through terminal OX.