Ford 3S4Z-9F472-DA
Oxygen Sensor, Front

Service of the Heated Oxygen Sensor (HO2S) begins with disconnecting the electrical connector after removing the wiring retainer. The use of penetrating and lock lubricant with thread application will help remove the sensor. A technician should employ the Exhaust Gas Oxygen Sensor Socket when removing the HO2S. Set the torque wrench properly then use it to tighten the sensor to 48 Nm (35 lb-ft) when installing. The sensor wires must follow paths that keep them safe from heat sources and metal edges to avoid damage. A thin layer of anti-seize lubricant should be applied to HO2S threads before engaging the electrical connector locking tab. Close the automotive task by following the reverse order of the removal process.