GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2001 🢒 Catera 🢒 Engine 🢒 Engine Controls - 3.0L (L81) 🢒 Intake Plenum Replacement

Removal Procedure
  1. Remove the intake plenum air inlet hose clamps and hoses from the throttle body.

    2. Object Number: 345354 Size: SH
  2. Remove the brake booster vacuum fitting (2) from the intake plenum.
  3. Remove the wiring harness channel bolts (1) and position the channel out of the way.

    4. Object Number: 349112 Size: SH
  4. Disconnect the electrical connector (1) and vacuum hose (2) from the switch-over valve on the back of the plenum.

    5. Object Number: 345338 Size: SH
  5. Disconnect the throttle body control electrical connector.
  6. Remove the throttle body bolts.

    7. Object Number: 345341 Size: SH
  7. Remove the throttle body from the plenum.

    8. Object Number: 345864 Size: SH
  8. Remove the crankcase vent tube adapter cover by gently prying up on the side.
  9. Remove the crankcase vent tube adapter screws from the plenum and position the adapter out of the way.
  10. Unclip the heater hose retaining clamp from the bracket on the right side of the plenum and position the heater hoses out of the way.

    11. Object Number: 345356 Size: SH
  11. Remove the intake plenum bolt caps.
  12. Remove the intake plenum bolts.
  13. Remove the intake plenum.
  14. Remove the intake plenum O-rings.

Installation Procedure
  1. Remove the masking from the intake plenum ports and ensure the sealing surfaces are clean and dry.
  2. Lightly coat the intake plenum O-rings with engine oil and install in the intake manifold.

    3. Object Number: 345356 Size: SH
  3. Install the intake plenum to the intake manifold. Ensure the alignment pins are properly seated.

    4. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  4. Install the intake plenum bolts.

    5. Tighten
    Tighten the intake plenum bolts to 20 N·m (15 lb ft).

  5. Install the intake plenum bolt caps.
  6. Install the heater hoses into the retaining clamp on the right side of the plenum and snap the retainer closed.

    7. Object Number: 345864 Size: SH
  7. Inspect and lightly lubricate with engine oil the seals on the crankcase vent tube adapter.
  8. Install the crankcase vent tube adapter and screws.

    9. Tighten
    Tighten the crankcase vent tube adapter screws to 8 N·m (71 lb in).

  9. Install the crankcase vent tube adapter cover and snap into place.

    10. Object Number: 345341 Size: SH
  10. Inspect the throttle body O-ring seals and replace if necessary.
  11. Install the throttle body.
  12. Install the throttle body bolts.

    13. Tighten
    Tighten the throttle body bolts to 12 N·m (106 lb in).


    Object Number: 345338 Size: SH
  13. Connect the throttle body control electrical connector.

    14. Object Number: 349112 Size: SH
  14. Connect the electrical connector (1) and vacuum hose (2) to the switch-over valve on the back of the plenum.

    15. Object Number: 345354 Size: SH
  15. Install the wiring harness channel and bolts (1).

    16. Tighten
    Tighten the wiring harness channel bolts to 8 N·m (71 lb in).

  16. Install the brake booster vacuum fitting (2) to the intake plenum.

    17. Tighten
    Tighten the brake booster vacuum fitting until fully seated and not stripped.

  17. Install the intake plenum air inlet hoses to the throttle body and tighten the clamps.