GM Service Manual Online
For 1990-2009 cars only

Important: Pinpoint the leak area before making any repairs. Random repairs may only temporarily restrict water entry and may make future diagnosis and repair more difficult.

Localized testing may be performed using either water or air.

  1. Begin the test at the base of the suspected leak area and continue upward slowly until the leak is located.
  2. Continue localized testing in the same general area in order to confirm that all possible leaks have been located.

To perform a localized leak test using water, refer to Water Hose Test . To perform a localized leak test using air, refer to Air Hose Test .