Exhaust Manifold Replacement - Left
Exhaust Manifold Replacement- LeftRemoval Procedure
Caution: Refer to Exhaust Service Caution in Service Precautions.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable.
2. Remove the front suspension support brace.
3. Remove the fuel rail cover.
4. Lift the locking lever on the mass air flow (MAF) sensor, then disconnect the MAP sensor electrical connector (1).
5. Lift the locking lever on the intake air temperature (IAT) sensor, then disconnect the IAT sensor electrical connector (2).
6. Loosen the 2 intake duct clamps (3), then remove the duct.
7. Relieve the fuel pressure.
8. Partially drain the cooling system.
9. Remove the coolant temperature sensor (1) to avoid possible damage during exhaust manifold removal.
10. Raise and support the vehicle. Refer to Vehicle Lifting.
Important: Use caution not to damage the oxygen sensors while removing the exhaust manifolds.
11. Remove the exhaust manifold to exhaust pipe flange nuts.
12. Lower the vehicle, then remove the spark plugs.
13. Progressively loosen, then remove the exhaust manifold bolts (1), working from the outside to center.
14. Remove the exhaust manifold and gasket from the cylinder head.
15. If equipped, remove the heat shield retaining bolts (1) and the heat shield from the exhaust manifold.
Installation Procedure
Important: Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may effect vehicle emissions and/or On-Board Diagnostics (OBD) II system performance.
The cylinder head exhaust manifold bolt hole threads must be cleaned and free of debris or threadlocking material.
1. If removed, position the heat shield to the exhaust manifold.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the heat shield to exhaust manifold bolts.
^ Tighten the heat shield to the exhaust manifold bolts to 9 Nm (80 inch lbs.).
3. Position the exhaust manifold and new gasket to the cylinder head.
Important: Do not apply thread sealant to the first 3 threads of the exhaust manifold bolts.
4. Apply a 5 mm (0.2 inch) wide band of threadlocker GM P/N 12345493 (Canadian P/N 10953488), or equivalent, to the threads of the exhaust manifold bolts.
5. Progressively torque the exhaust manifold bolts from the center to the outsides using 2 steps.
5.1. Tighten the exhaust manifold bolts first pass to 15 Nm (11 ft. lbs.).
5.2. Tighten the exhaust manifold bolts second pass to 25 Nm (18 ft. lbs.).
6. Bend over the exposed edge of the exhaust manifold gasket at the rear of the cylinder head.
7. Install the spark plugs.
8. Raise and support the vehicle. Refer to Vehicle Lifting.
9. Install the exhaust manifold to exhaust pipe flange nuts.
^ Tighten the exhaust manifold to exhaust pipe flange nuts to 25 Nm (18 ft. lbs.).
10. Lower the vehicle, then install the coolant temperature sensor (1).
^ Torque the coolant temperature sensor to 20 Nm (15 ft. lbs.).
11. Refill the cooling system.
12. Position the intake duct then install 2 intake duct clamps (3).
13. Connect the IAT sensor electrical connector (2).
14. Connect the MAP sensor electrical connector (1).
15. Install the fuel rail cover.
16. Install the front suspension support brace.
Caution: Refer to Exhaust Service Caution in Service Precautions.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
17. Connect the negative battery cable.