Inspection Procedure
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- Inspect the manifold for the following conditions:
- Damaged gasket or sealing surfaces
- Loose threaded inserts or studs
- Debris or restrictions within the passages of the manifold
- Damaged or broken vacuum fittings
- Inspect the composite intake manifold assembly for cracks or other damage.
- Inspect the intake manifold cylinder head deck for warpage.
- Locate a straight edge across the intake manifold cylinder head deck surface.
Position the straight edge across a minimum of two runner port openings.
- Insert a feeler gauge between the intake manifold and the straight edge.
An intake manifold with warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area is warped and should be replaced.
- Locate a straight edge across the intake manifold cylinder head deck surface.