For 1990-2009 cars

1. Clean the intake manifold and the mating surfaces.
2. Inspect the intake manifold for the following:

• | Damage

• | Cracks near the mounting holes

• | Blockage in the crankcase ventilation passages

3. Use a straight edge and a feeler gage and measure the intake manifold mounting surface for warpage.

Intake Manifold Maximum Warpage
0.10 mm (0.004 in)

4. If the warpage is greater than the maximum, replace the intake manifold.