Heated Oxygen Sensor Control

Oxygen content of exhaust gases is detected by oxygen sensor(s) located in exhaust manifold(s). This sensor converts percentage of oxygen present in exhaust gases into an electrical signal that is transmitted to PCM.

The PCM uses this information to determine air/fuel ratio and adjusts injector timing (pulse width) to obtain a 14.7:1 air/fuel ratio. Oxygen sensor signal (closed loop mode) is also used for regulation of fuel tank (evaporative) control valve.

If fault code is set or if oxygen sensor is malfunctioning, PCM will operate engine at an oxygen sensor substitute value of.45 volt.