I think two, part number 25312200
REMOVAL PROCEDURE
TOOLS REQUIRED
J 39194 Oxygen Sensor Wrench
NOTE: Do not remove this pigtail from either the heated oxygen sensor (HO2S) or the oxygen sensor (O2S). Removing the pigtail or the connector will affect sensor operation.
Handle the oxygen sensor carefully. Do not drop the HO2S. Keep the in-line electrical 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, connector or terminals. Replace the oxygen sensor if the pigtail wiring, connector, or terminal is damaged.
This external clean air reference is obtained by way of the oxygen sensor signal and heater wires. Any attempt to repair the wires, connectors, or terminals could result in the obstruction of the air reference and degraded sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors. These materials may get into the sensor causing poor performance.
Do not damage the sensor pigtail and harness wires in such a way that the wires inside are exposed. This could provide a path for foreign materials to enter the sensor and cause performance problems.
Ensure the sensor or vehicle lead wires should not be bent sharply or kinked. Sharp bends or kinks could block the reference air path through the lead wire.
Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize the ground wired sensor may rely on this ground as the only ground contact to the sensor. Removal of the ground wire will cause poor engine performance.
Ensure that the peripheral seal remains intact on the vehicle harness connector in order to prevent damage due to water intrusion. The engine harness may be repaired using Packard's Crimp and Splice Seals Terminal Repair Kit. Under no circumstances should repairs be soldered since this could result in the air reference being obstructed.
The Heated Oxygen Sensor (HO2S) 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 the exhaust pipe.
Disconnect the negative battery cable.
Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Remove the HO2S sensor connector heat shield if necessary.
Remove the HO2S sensor harness connector.
Carefully remove the heated oxygen sensor using a J 39194 Oxygen Sensor Wrench
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the Heated Oxygen Sensor (HO2S) threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an engine and if for any reason it is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.
Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695 or the equivalent if necessary. NOTE: Refer to Component Tightening Notice in Cautions and Notices.
Install the sensor using a J 39194 Oxygen Sensor Wrench. Tighten Tighten the sensor to 41 N.m (30 lb ft)
Install the HO2S sensor harness connector.
Install the HO2S sensor connector heat shield if necessary.
Lower the vehicle.
Connect the negative battery cable.
