Intake Manifold Cleaning and Inspection

CAUTION: Refer to SAFETY GLASSES CAUTION in Cautions and Notices.

Clean the upper intake manifold in cleaning solvent.
Dry the upper intake manifold with compressed air.

Fig 1: Upper Intake Manifold
Courtesy of GENERAL MOTORS CORP.
Clean the lower intake manifold in cleaning solvent.
Dry the lower intake manifold with compressed air.

Fig 2: Lower Intake Manifold
Courtesy of GENERAL MOTORS CORP.
Inspect the upper intake manifold for the following:
- Cracks or other damage to the exterior (1)
- Cracking or damage in the gasket grooves (2) and (3)
- Damage to the throttle body mounting surface (4)
- Loose or damaged bolt hole thread inserts (5)
Fig 3: Upper Intake Manifold Inspection Areas
Courtesy of GENERAL MOTORS CORP.
Inspect the lower intake manifold for the following:
- Damage to the gasket sealing surfaces (1), (2) and (3)
- Restricted exhaust gas recirculation (EGR) system passages (4)
- Restricted cooling system passages (5)
- Cracks or damage
- Damage to the threaded bolt holes
Fig 4: Lower Intake Manifold Inspection Areas
Courtesy of GENERAL MOTORS CORP.