Intake Manifold Cleaning and Inspection

WARNING: This page is about a different car, the 2004 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Intake Manifold Bolts And Nuts

Courtesy of GENERAL MOTORS CORP.

Inspect the intake manifold for damage.
Inspect the intake manifold for cracks near the mounting holes (1-4).
Inspect the crankcase ventilation passages for any blockage and clean as necessary.

Fig 2: Intake Manifold Mating Surfaces

Courtesy of GENERAL MOTORS CORP.

Clean the intake manifold mating surfaces.
Use a straight edge and a feeler gage and measure the intake manifold mounting surface for warpage.
Intake Manifold Maximum Warpage: 0.10 mm (0.0039 in)
If the warpage is greater than the maximum, replace the intake manifold.