C 3500 HD Truck 2WD V8-8.1L VIN G (2002)
Oxygen Sensor: Service and Repair
Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1
TOOLS REQUIRED
J 39194-B Heated Oxygen Sensor Wrench
REMOVAL PROCEDURE
IMPORTANT: The heated oxygen sensor may be difficult to remove when the engine temperature is below 48°C (120°F). Excessive force may
damage the threads in the exhaust manifold or exhaust pipe. Lowering the exhaust system may be necessary to gain sufficient access to a HO2S and/or
a HO2S connector.
1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
2. Disconnect the HO2S electrical connector (2).
NOTE: 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. A dropped oxygen sensor is a bad oxygen sensor.
3. Using the J 39194-B loosen the heated oxygen sensor (1).
4. Carefully back out the heated oxygen sensor.