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Home >> Cadillac >> 2003 >> CTS Standard >> Repair and Diagnosis >> Engine Mechanical >> Engine Mechanical - 3.2L >> Repair Instructions >> On-Vehicle Repair Instructions >> Intake Plenum Replacement >> Installation Procedure
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Installation Procedure

  1. Assemble the intake plenum if necessary. Refer to INTAKE PLENUM MANIFOLD ASSEMBLE .
  2. Remove the masking from the intake plenum ports and ensure the sealing surfaces are clean and dry.
  3. Lightly coat the intake plenum O-ring seals with clean engine oil and install to the intake manifold.
  4. Position the intake plenum to the intake manifold, aligning the pins.
    NOTE: Refer to FASTENER NOTICE in Cautions and Notices.
  5. Install the intake plenum bolts.

    Tighten 

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

  6. Install the intake plenum bolt caps.
    Fig 1: Installing Intake Plenum Bolts & Caps
    G02085851Courtesy of GENERAL MOTORS CORP.
  7. Install the 2 bolts securing the ECM bracket to the intake plenum.

    Tighten 

    Tighten the ECM bracket bolts to 8 N.m (71 lb in) in sequence 2-3.

    Fig 2: Installing Engine Control Module (ECM) Bracket & Retaining Bolts
    G02085852Courtesy of GENERAL MOTORS CORP.
  8. Connect the vacuum brake booster hose (3) to the vacuum source.
  9. Install the bolt (1) securing the throttle body heater inlet hose/pipe to the intake plenum (2).

    Tighten 

    Tighten the throttle body heater inlet hose/pipe bolt to 9 N.m (80 lb in).

    Fig 3: Installing Throttle Body Heater Inlet Hose Mounting Bolt & Brake Booster Hose
    G02085853Courtesy of GENERAL MOTORS CORP.
  10. Connect the electrical connector (1) and vacuum hose (2) to the switchover valve at the rear of the plenum.
    Fig 4: Connecting Switchover Valve Electrical Connector & Vacuum Hose
    G02085854Courtesy of GENERAL MOTORS CORP.
  11. Position the remote power steering fluid reservoir (2) to the engine.
  12. Install the remote power steering fluid reservoir mounting bolts (1, 3).

    Tighten 

    • Tighten the remote power steering fluid reservoir mounting bolts (1) to intake plenum to 9 N.m (80 lb in).
    • Tighten the remote power steering fluid reservoir mounting bolt (3) to cylinder head to 25 N.m (18 lb ft).
      Fig 5: Installing Remote Power Steering Fluid Reservoir Mounting Bolts
      G02085855Courtesy of GENERAL MOTORS CORP.
  13. Connect the vacuum brake booster hose retainer (1) to the rear of the intake plenum- RHD only.
  14. Connect the crankcase ventilation dirty air hose retainer (2) to the fuel pipe.
    Fig 6: Installing Vacuum Brake Booster Hose Retainer
    G02085856Courtesy of GENERAL MOTORS CORP.
  15. Apply clean engine oil to the crankcase vent adapter seal.
  16. Position the crankcase vent adapter to the intake plenum.
  17. Install the 3 bolts securing the crankcase vent adapter to the intake plenum.

    Tighten 

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

    Fig 7: Installing Crankcase Vent Adapter & Mounting Bolts
    G02085857Courtesy of GENERAL MOTORS CORP.
  18. Inspect the following O-ring seals and replace if necessary:
    • The throttle body
    • The crankcase vent tubes
  19. Lightly lubricate the O-ring seals with clean engine oil.
  20. Position the throttle body to the intake plenum and crankcase vent adapter.
  21. Install the bolts securing the throttle body to the intake plenum.

    Tighten 

    Tighten the throttle body bolts to 8 N.m (71 lb in).

  22. Connect the fuel pressure regulator atmospheric vent tube to the bottom of the throttle body.
    Fig 8: Installing Bolts Securing Throttle Body To Intake Plenum
    G02085858Courtesy of GENERAL MOTORS CORP.
  23. Install the intake plenum air inlet hose clamps and hoses to the throttle body.
    Fig 9: Installing Intake Plenum Air Inlet Hoses & Clamps
    G02085859Courtesy of GENERAL MOTORS CORP.
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