GM Service Manual Online
For 1990-2009 cars only

Exhaust Manifold Cleaning and Inspection Left

Cleaning Procedure

  1. Clean the exhaust manifold in solvent.
  2. Caution: Wear safety glasses in order to avoid eye damage.

  3. Dry the exhaust manifold with compressed air.

Inspection Procedure


    Object Number: 576737  Size: SH
  1. Inspect the exhaust manifold for the following:
  2. • Damage or broken welds (1)
    • Damage or excessive corrosion to the exhaust manifold exterior (1)
    • Damage to the heat shield brackets (2)

    Object Number: 576679  Size: SH
  3. Inspect the exhaust manifold for the following:
  4. • Damage to the exhaust manifold flange bolt holes (1)
    • Damage to the exhaust crossover sealing area (2)
    • Damage to the exhaust crossover gasket (3)
    • Damage to the exhaust manifold mounting holes (4)
    • Damage to the gasket sealing surfaces (5)
    • Damage or restrictions within the exhaust passages (6)
  5. Repair or replace the exhaust manifold and/or components as necessary.

  6. Object Number: 576682  Size: SH
  7. Measure the alignment or surface flatness of the exhaust manifold flanges, using a straight edge and a feeler gauge. Exhaust manifold surface flatness must not exceed 0.254 mm (0.010 in).
  8. If the surface flatness is not within specifications, the exhaust manifold is warped and must be replaced.

Exhaust Manifold Cleaning and Inspection Right

Cleaning Procedure

  1. Clean the exhaust manifold in solvent.
  2. Caution: Wear safety glasses in order to avoid eye damage.

  3. Dry the exhaust manifold with compressed air.

Inspection Procedure


    Object Number: 576683  Size: SH
  1. Inspect the exhaust manifold for the following:
  2. • Damage to the pipe flare (1)
    • Damage to the pipe flange (2)
    • Damage or excessive corrosion to the exhaust manifold exterior (3)
    • Damage to the converter pipe studs (4)
    • Damage to the converter pipe gasket sealing surfaces (5)

    Object Number: 576687  Size: SH
  3. Inspect the exhaust manifold for the following:
  4. • Damage to the oxygen sensor threaded hole (1)
    • Damage to the EGR pipe fitting (2)
    • Damage to the exhaust manifold mounting holes (3)
    • Damage to the gasket sealing surfaces (4)
    • Damage or restrictions within the exhaust passages (5)
    • Damage or broken welds
  5. Repair or replace the exhaust manifold and/or components as necessary.

  6. Object Number: 576690  Size: SH
  7. Measure the alignment or surface flatness of the exhaust manifold flanges, using a straight edge and a feeler gauge. Exhaust manifold surface flatness must not exceed 0.254 mm (0.010 in).
  8. If the surface flatness is not within specifications, the exhaust manifold is warped and must be replaced.