C 1500 Truck 2WD V8-5.3L VIN T (1999)
Oxygen Sensor: Service and Repair
HO2S Replacement Bank 1
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.
IMPORTANT: Take care when handling the heated oxygen sensor. The in-line electrical connector and louvered end must be kept free of grease, dirt
or other contaminants. Also, avoid using cleaning solvents of any type. Do not drop or roughly handle the heated oxygen sensor. A dropped sensor is a
bad sensor.
REMOVAL PROCEDURE
NOTE: Removal of the oxygen sensor is easier when the engine temperature is above 48°C (120°F). Excessive force may damage the threads in the
exhaust pipe. It may be necessary to lower the exhaust system to gain sufficient access to a HO2S and/or it's connector. Refer to Engine Exhaust
1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Determine the location of the HO2S to be removed. Refer to Engine Controls Component Views.
3. Disconnect the HO2S electrical connector.
4. Carefully back out the heated oxygen sensor.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor threads. The compound consists of graphite suspended in fluid
and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New or service sensors will already
have the compound applied to the threads. If a sensor is removed from an engine and if for any reason is to be reinstalled, the threads must have
anti-seize compound applied before reinstallation.
