Envoy 4WD V8-5.3L VIN M (2005)
1. Connect the HO2S electrical connector (2).
2. Install the CPA retainer.
3. Install the catalytic converter.
4. If reinstalling the old sensor, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.
IMPORTANT: A special anti-seize compound is used on the 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 exhaust component and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
5. Install the HO2S (2).
IMPORTANT: If the HO2S sensor is connected to the main wiring harness during installation. Rotate the HO2S sensor several turns
counterclockwise before threading the HO2S sensor into the catalytic converter. This action of initially reverse winding of the pigtail wires will
prevent a condition where the HO2S sensor pigtail wires become severely twisted or binding once the HO2S sensor is installed into the catalytic
converter.
Tighten the sensor to 42 N.m (31 lb ft).
