Downstream Heated Oxygen Sensor: Removal
WARNING: This page is about a different car, the 2003 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
The heated oxygen sensors each use a permanently attached pigtail and connector. Do not remove the pigtail from the heated oxygen sensor. Damage or removal of the pigtail or the connector affects proper operation of the heated oxygen sensor. Handle the oxygen sensor carefully. Do not drop the oxygen sensor. Keep the in-line connector and the louvered end free of grease, dirt or other contaminants. Do not use cleaning solvents of any type. Do not repair the wiring, the connector, or the terminals. Replace the oxygen sensor if the pigtail wiring, the terminals, or the connector is damaged. Proper oxygen sensor operation requires an external air reference. This external air reference is obtained by way of the oxygen sensor signal and heater wires. Any attempt to repair the wires, the connectors, or the terminals results in the obstruction of the air reference and degrades the oxygen sensor performance. The heated oxygen sensor may be difficult to remove when the engine temperature is below 120°F (48°C). Excessive force may damage threads in the exhaust manifold or exhaust pipe.
Downstream Heated Oxygen Sensor (HO2S) may also be referred to as bank 1 sensor 2. Turn ignition off. Bank 1 sensor 2 is located behind catalytic converter. See Figure . Raise and support vehicle. Disconnect bank 1 sensor 2 harness connector. Using HO2S Wrench (J-39194-B), carefully remove bank 1 sensor 2 from exhaust pipe.