Oxygen (O2) Sensor

O2 sensor is mounted in exhaust manifold or exhaust pipe, where it contacts exhaust gases. O2 sensor generates voltage according to oxygen content in exhaust gases. Voltage will vary from .1 volt (lean condition) to as high as one volt (rich condition).

Sensor will not generate a voltage signal until it reaches operating temperature. Sensor sends voltage signal to ECM, which uses it to obtain correct emissions by adjusting air/fuel ratio. Until sensor is warmed up, ECM adjusts air/fuel mixture based upon preprogrammed ECM memory.

On Tracker, a heated oxygen sensor is used. This sensor works the same way as the non-heated sensor, except the O2 sensor is heated for more precise determination of exhaust gas oxygen concentration.