GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 318859  Size: SH
  1. Open the rear compartment.
  2. Remove the rear bumper fascia. Refer to Fascia, Fascia Energy Absorber, Impact Bar, Fascia Bracket Replacement - Rear in Bumpers.
  3. Pull back the rear compartment trim panel.
  4. Apply pressure at 2 upper locations and 2 lower locations, using a small, flat-bladed tool in order to release the retainers on the pressure relief valve.
  5. Remove the pressure relief valve from the lower quarter panel.

Installation Procedure


    Object Number: 318859  Size: SH
  1. Install the pressure relief valve to the lower quarter panel.
  2. Press the pressure relief valve into the quarter lower panel until the retainers lock into place at the upper and lower locations.
  3. Pull back the rear compartment trim panel.
  4. Install the rear bumper fascia. Refer to Fascia, Fascia Energy Absorber, Impact Bar, Fascia Bracket Replacement - Rear in Bumpers.
  5. Close the rear compartment.