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For 1990-2009 cars only

Exhaust Manifold Replacement - Left Side LA3, LY9

Removal Procedure

Caution: Refer to Exhaust Service Caution in the Preface section.

Caution: Refer to Protective Goggles and Glove Caution in the Preface section.

  1. Remove the accessory mounting bracket. Refer to Accessory Mounting Brackets Replacement in Engine Mechanical-2.6L and 3.2L.

  2. Object Number: 785786  Size: SH
  3. Disconnect the heated oxygen sensor pigtail (1) from the wiring harness connector (2).
  4. Remove the left catalytic converter. Refer to Catalytic Converter Replacement - Left Side .
  5. Remove the heated oxygen sensor if replacement is necessary. Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 in Engine Controls-2.6L and 3.2L.

  6. Object Number: 815455  Size: SH
  7. Remove the left exhaust manifold retaining nuts.
  8. Remove the left exhaust manifold and the gasket from the engine. Do not reuse the gasket.
  9. Clean and inspect the left exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection in Engine Mechanical-2.6L and 3.2L.

Installation Procedure


    Object Number: 815455  Size: SH
  1. Place a NEW exhaust manifold gasket over the cylinder head studs.
  2. Position the left exhaust manifold to the left cylinder head.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the left exhaust manifold nuts.
  5. Tighten
    Tighten the exhaust manifold nuts to 20 N·m (15 lb ft).

  6. Install the heated oxygen sensor if previously removed. Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 in Engine Controls-2.6L and 3.2L.
  7. Install the left catalytic converter. Refer to Catalytic Converter Replacement - Left Side .

  8. Object Number: 785786  Size: SH
  9. Connect the heated oxygen sensor pigtail (1) to the wiring harness connector (2).
  10. Install the accessory mounting bracket. Refer to Accessory Mounting Brackets Replacement in Engine Mechanical-2.6L and 3.2L.

Exhaust Manifold Replacement - Left Side LY7

Removal Procedure

Caution: Refer to Exhaust Service Caution in the Preface section.

Caution: Refer to Protective Goggles and Glove Caution in the Preface section.

  1. Remove the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement - Left Side .
  2. Remove the oil level indicator. Refer to Oil Level Indicator and Tube Replacement .

  3. Object Number: 1221180  Size: SH
  4. Remove the catalytic converter nuts.

  5. Object Number: 902880  Size: SH
  6. Remove the exhaust manifold bolts.
  7. Important: Do not reuse the gasket.

  8. Remove the exhaust manifold and discard the exhaust manifold gasket.
  9. Clean and inspect the exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection - Left Side .

Installation Procedure

    Important: Inspect the catalytic converter seal/heat shield sealing surface. Replace the seal/heat shield if the sealing surface is worn or damaged.

  1. Install the catalytic converter seal/heat shield to the catalytic converter.

  2. Object Number: 902880  Size: SH
  3. Install a NEW exhaust manifold gasket to the exhaust manifold.
  4. Install the exhaust manifold with the gasket to the catalytic converter and the cylinder head.
  5. Notice: Refer to Fastener Notice in the Preface section.

  6. Install the exhaust manifold bolts.
  7. Tighten
    Tighten the exhaust manifold bolts to 20 N·m (15 lb ft).


    Object Number: 1221180  Size: SH
  8. Install the catalytic converter nuts.
  9. Tighten
    Tighten the catalytic converter nuts to 50 N·m (37 lb ft).

  10. Install the oil level indicator. Refer to Oil Level Indicator and Tube Replacement .
  11. Install the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement - Left Side .

Exhaust Manifold Replacement - Left Side LS6

Removal Procedure


    Object Number: 1455615  Size: SH
  1. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 5.7L.
  2. Remove the left bank coil assembly. Refer to Ignition Coil Replacement in Engine Controls - 5.7L.
  3. Remove the left bank spark plugs. Refer to Spark Plug Replacement in Engine Controls - 5.7L.
  4. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  5. Remove the left catalytic converter. Refer to Catalytic Converter Replacement - Left Side .

  6. Object Number: 1199291  Size: SH
  7. Disconnect the center steering shaft from the lower steering shaft. Separate the shafts and position aside to provide a removal envelope for the manifold. Refer to Intermediate Steering Shaft Replacement - Center in Steering Wheel and Column.
  8. Lower the vehicle.
  9. Remove the exhaust manifold bolts.
  10. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  11. Remove the exhaust manifold, bolts, and gasket. Discard the gasket.
  12. Remove the heat shield from the manifold, if required.
  13. Clean and inspect the exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection in Engine Mechanical - 5.7L.

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.

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1199291  Size: SH
  1. If necessary, install the exhaust manifold heat shield and bolts.
  2. Tighten
    Tighten the exhaust manifold heat shield bolts to 9 N·m (80 lb in).

  3. Position the exhaust manifold and a NEW gasket into place.
  4. Lower the vehicle.
  5. Install the exhaust manifold bolts. Refer to Exhaust Manifold Installation - Left Side in Engine Mechanical - 5.7L.
  6. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  7. Connect the center steering shaft to the lower steering shaft. Refer to Intermediate Steering Shaft Replacement - Center in Steering Wheel and Column.

  8. Object Number: 1455615  Size: SH
  9. Install the left catalytic converter. Refer to Catalytic Converter Replacement - Left Side .
  10. Lower the vehicle.
  11. Install the left bank spark plugs. Refer to Spark Plug Replacement in Engine Controls - 5.7L.
  12. Install the left bank coil assembly. Refer to Ignition Coil Replacement in Engine Controls - 5.7L.
  13. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 5.7L.