GM Service Manual Online
For 1990-2009 cars only

Interior windnoise is not heard when the window is lowered. Interior windnoise is caused by the air leaving the inside of the vehicle through a seal or a seam.

  1. Tape over the relief valves to cause added air pressure within the vehicle.
  2. Test drive the vehicle and listen for windnoise or a whistle.
  3. Pull the vehicle over and make the temporary repairs using masking tape. If you cannot determine the source of the windnoise, perform one or more of the following diagnostic tests:
  4. •  Tracing Powder or Chalk Test .
    •  Air Pressure Test .
    •  Soap Suds or Bubble Test .