Exhaust Manifold Replacement - Left Side 4.3L

1. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Resonator Replacement in Engine Controls-4.3 L.
2. Remove the intermediate steering shaft. Refer to Lower Intermediate Steering Shaft Replacement in Steering Wheel and Column - Standard.



3. Disconnect the engine coolant temperature (ECT) sensor electrical connector.



4. Remove the exhaust gas recirculation (EGR) valve inlet pipe from the exhaust manifold.



5. Remove the radiator inlet hose support bracket nut.



6. Remove the nuts holding the secondary air injection (AIR) pipe to the exhaust manifold, if equipped.
7. Remove the AIR pipe and gasket from the exhaust manifold.
8. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
9. Remove the exhaust pipe from the exhaust manifold. Refer to Exhaust Manifold Pipe Replacement .
10. Lower the vehicle to the proper height.
11. Remove the left front tire to gain access to the rear exhaust manifold bolts. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.



12. Remove the fender wheelhouse extension.
13. Working through the wheel house opening disconnect the spark plug wires from the spark plugs.

13.1.

Rotate the spark plug wire boot one half turn.

13.2.

Pull outward on the spark plug wire boot to release from the spark plug.




14. Remove the exhaust manifold bolts and the stud.
15. Lower the vehicle.
16. From under the hood remove the exhaust manifold and the spark plug wire shields from the engine.



17. Remove and discard the exhaust manifold gaskets.
18. Clean The exhaust manifold gasket mating surfaces. Refer to Exhaust Manifold Cleaning and Inspection in Engine Mechanical - 4.3 L Unit Repair.

Important: To assist in installing the exhaust manifold to the engine, the tabs on a NEW exhaust manifold gasket will hold the gasket and bolts in place.

1. Install the exhaust manifold gaskets to the exhaust manifold.
2. Position the exhaust manifold to the engine.
3. Raise the vehicle to the proper height.



4. Working through the wheelhouse opening, install the exhaust manifold.
5. Install the spark plug wire shields.
6. Apply threadlock GM P/N 12345493 or equivalent to the threads of the exhaust manifold bolts and stud.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

7. Install the exhaust manifold bolts and stud.

Tighten

1. Tighten the exhaust manifold bolts and stud on the first pass to 15 N·m (11 lb ft).
2. Tighten the exhaust manifold bolts and stud on the final pass to 30 N·m (22 lb ft).
8. Install the spark plug wires to the spark plug wire retainers.
9. Install the spark plug wires onto the spark plugs.



10. Install the fender wheelhouse extension.
11. Install the left front tire. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
12. Raise the vehicle.
13. Install the exhaust pipe to the exhaust manifold. Refer to Exhaust Manifold Pipe Replacement .
14. Lower the vehicle.



15. Install the EGR valve inlet pipe to the exhaust manifold.

Tighten
Tighten the EGR valve inlet pipe nut to 30 N·m (22 lb ft).




16. Connect the engine coolant temperature (ECT) sensor electrical connector.



17. Install a new AIR pipe gasket and the AIR pipe to the exhaust manifold.
18. Install the AIR pipe nuts.

Tighten
Tighten the AIR pipe nuts to 25 N·m (18 lb ft).




19. Install the radiator inlet hose support bracket and nut.

Tighten
Tighten the radiator inlet hose support bracket nut to 36 N·m (27 lb ft).

20. Install the intermediate steering shaft. Refer to Lower Intermediate Steering Shaft Replacement in Steering Wheel and Column - Standard.
21. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Resonator Replacement in Engine Controls-4.3 L.