Oxygen Sensor

The oxygen sensor, located in the exhaust manifold, is used by the MCU to determine oxygen content of exhaust gases. The sensor sends a voltage signal to the MCU that is proportional to the oxygen content of exhaust gases. When higher amounts of oxygen are detected in the exhaust gases (lean mixture indicated), the electrical signal generated by the sensor drops in voltage. A lower oxygen content (rich mixture indicated) causes an increase in voltage signal output.