For 1990-2009 cars

### Removal Procedure

Caution: In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable.
2. Disconnect the heated oxygen sensor (HO2S1) electrical connector.
3. Remove the following from the exhaust manifold (2):

• | 2 nuts

• | 3 bolts

• | The upper exhaust manifold heat shield (1)

4. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
5. Remove the following from the exhaust manifold and engine block:

• | 2 bolts

• | 1 nut

• | The exhaust manifold reinforcement bracket (1)

6. Remove the following from the exhaust manifold (1):

• | 2 bolts

• | The front pipe/three way catalytic converter (TWC) assembly (3)

7. Lower the vehicle.
8. Remove the 9 nuts and the lift hook from the exhaust manifold (3).
9. Remove the exhaust manifold (3) with the gasket (2).
10. Remove the three bolts and lower the exhaust manifold heat shield (6) from the exhaust manifold (2).
11. Remove the heated oxygen (HO2S1) Sensor (4) from the exhaust manifold (2).
12. Remove the three way catalytic converter (TWC) front pipe gasket from the exhaust manifold (2).

### Installation Procedure

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.

1. Install the heated oxygen (HO2S1) sensor (4) into the exhaust manifold (2).

Tighten
Tighten the (HO2S1) Sensor to 43 N·m (32 lb ft).

2. Install the 3 bolts and lower the exhaust manifold heat shield (6) to the exhaust manifold (2).

Tighten
Tighten the lower manifold heat shield bolts to 10 N·m (89 lb in).

3. Install the new exhaust manifold gasket (2) and the exhaust manifold (3).
4. Install the engine hanger (3) to the cylinder head. Secure the exhaust manifold and hanger with 9 nuts (1).

Tighten
Tighten the exhaust manifold nuts to 23 N·m (17 lb ft).

5. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
6. Install the front pipe/TWC assembly (3) with a new gasket (2) to the exhaust manifold (1). Secure the assembly with 2 bolts.

Tighten
Tighten the exhaust manifold-to-front pipe/TWC assembly bolts to 50 N·m (37 lb ft).

7. Install the exhaust manifold brackets (1) to the exhaust manifold and the engine block. Secure the brackets with 1 nut and 2 bolts.

#### Tighten

• | Tighten the engine mount-to-exhaust bracket bolts to 54 N·m (40 lb ft).

• | Install the exhaust bracket-to-exhaust manifold nut to 50 N·m (37 lb ft).

8. Lower the vehicle.
9. Install the upper exhaust manifold heat shield (1) to the exhaust manifold. Secure the heat shield with 2 nuts and 3 bolts.

Tighten
Tighten the upper exhaust manifold heat shield nuts and bolts to 10 N·m (89 lb in).

10. Connect the (HO2S1) electrical connector.
11. Connect the negative battery cable.

Tighten
Tighten the negative battery cable bolt to 15 N·m (11 lb ft).