Caution: The exhaust temperature sensor and exhaust pressure differential sensor line fittings may be difficult to remove when the engine exhaust system temperature is below 48°C (120°F). Excessive force may damage the threads in the exhaust manifold or exhaust pipe.

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
2. Reposition the exhaust differential pressure sensor pipe assembly hose clamps (1).
3. Remove the exhaust differential pressure sensor pipe assembly hoses from the sensor and hose bracket.



4. Remove the exhaust pressure differential sensor pipe clip bolt (1).



5. Loosen the exhaust pressure differential sensor pipe fitting at the exhaust particulate filter.
6. Remove the exhaust pressure differential sensor position 1 pipe (1) from the exhaust particulate filter.



7. Loosen the exhaust pressure differential sensor pipe fitting at the exhaust particulate filter.
8. Remove the exhaust pressure differential sensor position 2 pipe (1) from the exhaust particulate filter.



9. Remove the exhaust pressure differential sensor pipe assembly from the vehicle.

Note: A special anti-seize compound is used in the sensor or line fittings threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor or line fitting easier to remove. New, or service replacement sensors or line fittings already have the compound applied to the threads. If the sensor or line fittings are removed from an exhaust component and if for any reason the sensor or line fitting are reinstalled, the threads must have anti-seize compound applied before reinstallation.

1. If reinstalling the old temperature sensor or differential pressor sensor line fittings, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.



2. Install the exhaust pressure differential sensor pipe assembly to the vehicle.



3. Position the exhaust pressure differential sensor position 2 pipe (1) to the exhaust particulate filter.

Caution: Refer to Fastener Caution in the Preface section.

4. Tighten the exhaust pressure differential sensor pipe fitting at the exhaust particulate filter.

Tighten
Tighten the fitting to 45 N·m (33 lb ft).




5. Position the exhaust pressure differential sensor position 1 pipe (1) to the exhaust particulate filter.
6. Tighten the exhaust pressure differential sensor pipe fitting at the exhaust particulate filter.

Tighten
Tighten the fitting to 45 N·m (33 lb ft).




7. Install the exhaust pressure differential sensor pipe clip bolt (1).

Tighten
Tighten the bolt to 9 N·m (80 lb in).




8. Install the exhaust differential pressure sensor pipe assembly hoses to the sensor and hose bracket.
9. Position the exhaust differential pressure sensor pipe assembly hose clamps (1).
10. Lower the vehicle.