Golf GTI L4-1781cc 1.8L SOHC (RD) (1987)
Oxygen Sensor: Description and Operation
Fig. 10 Oxygen (Lambda) Sensor
The oxygen sensor, Fig. 10, is constructed of Zirconium dioxide, and the inner and outer surfaces are coated with platinum. The outer platinum
surface is exposed to the exhaust gas while the inner surface is exposed to the outside air.
The oxygen sensor sends a variable voltage (0 - 1.0 VDC) to the electronic control unit depending on the difference between the amount of oxygen
contacting the inner and outer surfaces of the sensor. The electronic control unit can then control the amount of fuel supplied to the engine in relation to
oxygen content.