GM Service Manual Online
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.