Oxygen Sensor: Description and Operation

Exhaust System Component Layout:

The Heated Oxygen Sensor (HO2S) is located it the exhaust manifold (# 12 in image).

The Motronic Engine Control Module (ECM) regulates the amount of fuel injected into each cylinder is based on the voltage signal received from the oxygen sensor. If there is a failure in the oxygen sensor signal, oxygen sensor control and oxygen sensor adaptation is stopped. The Motronic control module will use the last learned input from the oxygen sensor as a fixed value. The evaporative emission control system is switched off also.