Nissan 22693-1AA0A Air Fuel Ratio Sensor

You need to keep the sensor and its connector clean and avoid using solvents. The silicone boot should be correctly installed. For upstream sensors, find the connector at the valve cover's rear, disconnect it, and unscrew the sensor with an oxygen sensor socket. Use anti-seize compound on the threads if reusing. For downstream sensors, raise the vehicle, locate the sensor, disconnect the connector, and loosen the sensor. Apply anti-seize if reusing. Installation is the reverse of removal, ensuring proper tightening.