F 150 Super Crew 4WD V8-5.4L Prop SOHC VIN Z (2003)
Oxygen Sensor: Description and Operation
Heated Oxygen Sensors
The compuvalve monitors upstream Heated Oxygen Sensors (HO2S). The upstream HO2S is used to control engine fuel flow. The sensor detects the
concentration of oxygen in the exhaust gas and sends a signal to the Powertrain Control Module (PCM) and to the compuvalve. In a rich condition,
the HO2S will output a voltage of 0.6 volt or greater, and in a lean condition a voltage of 0.4 volt or less will be output.
In the event that the HO2S fails, the Malfunction Indicator Lamp (MIL) will be illuminated.
