GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2000 🢒 Catera 🢒 Engine 🢒 Engine Controls - 3.0L (L81) 🢒 Intake Resonance Switchover Valve Replacement

Removal Procedure

    Object Number: 661778 Size: SH
  1. Loosen the hose clamps and remove the upper air ducts (1,2) that connect to the throttle body.
  2. Disconnect the vacuum hose (4) from the actuator diaphragm (12).
  3. Remove the intake air resonator nuts (9) that attaches the resonator to the fan shroud. This will allow access to the lower air duct clamps.
  4. Loosen the lower air duct clamps and remove the switchover valve assembly (3).

    5. Object Number: 661923 Size: SH
  5. Remove the bolts (1) that retain the valve in the housing.
  6. Remove the switchover valve from the housing.

Installation Procedure

    Object Number: 661923 Size: SH
  1. Install the switchover valve into the switchover valve housing.
  2. Install the bolts that retain the switchover valve in the housing.

    3. Tighten
    Tighten the bolts to 8 N·m (71 lb in).


    Object Number: 661778 Size: SH
  3. Install the switchover valve assembly (3) into the lower air duct clamps.

    4. Tighten
    Tighten the clamps to 3 N·m (27 lb in).

  4. Install the intake air resonator nut that attaches the resonator to the fan shroud.

    5. Tighten
    Tighten the nut to 3 N·m (27 lb in).

  5. Connect the vacuum hose to the actuator diaphragm.
  6. Install the upper air ducts that connect to the throttle body to the intake air resonance switchover valve assembly.

    7. Tighten
    Tighten the clamps to 3 N·m (27 lb in).

  7. Inspect for leaks.