GM Service Manual Online
For 1990-2009 cars only

    Object Number: 828279  Size: SH
  1. Inspect the intake manifold for damage.
  2. Inspect the intake manifold for cracks near the mounting holes (1-4).
  3. Inspect the crankcase ventilation passages for any blockage and clean as necessary.

  4. Object Number: 830823  Size: SH
  5. Clean the intake manifold mating surfaces.
  6. Use a straight edge and a feeler gage and measure the intake manifold mounting surface for warpage. Refer to Engine Mechanical Specifications .
  7. If the warpage is greater than the maximum, replace the intake manifold.