Civic DX Sedan L4-1668cc 1.7L SOHC MFI (2001)
Oxygen Sensor: Description and Operation
Third Heated Oxygen Sensor (Third HO2S)
Third Heated Oxygen Sensor (Third HO2S) (D17A6 engine)
The third HO2S detects the oxygen content in the exhaust gas downstream of the NOX Adsorptive Three Way Catalytic Converter (NOX Adsorptive
TWC) and sends signals to the ECM/PCM which varies the duration of fuel injection accordingly. To stabilize its output, the sensor has an internal
heater. The third HO2S is installed behind the NOX Adsorptive TWC.
