GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2007 🢒 CTS 🢒 Engine 🢒 Engine Mechanical - 2.8L (LP1) 🢒 Lower Intake Manifold Replacement

Removal Procedure

    Object Number: 1305320 Size: SH
  1. Turn the ignition OFF.
  2. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement .
  3. Remove the air inlet duct. Refer to Air Cleaner Inlet Duct Replacement .
  4. Disconnect the brake booster hose from the intake manifold.

    5. Object Number: 887878 Size: SH
  5. Disconnect the purge solenoid valve electrical connector.

    6. Object Number: 1348201 Size: SH
  6. Disconnect the purge line (3) from the purge solenoid valve.

    7. Object Number: 887871 Size: SH
  7. Disconnect the fuel injector harness electrical connector.

    8. Object Number: 887881 Size: SH
  8. Disconnect the throttle body electrical connector.

    9. Object Number: 1285256 Size: SH
  9. Remove the wiring harness retainer.

    10. Object Number: 1522522 Size: SH
  10. Remove the upper intake manifold brace bolt (2) and stud (1), reposition the brace with the wiring harness.
  11. Remove the wiring harness retainer from the right side of the throttle body.
  12. Disconnect the positive crankcase valve (PCV) hose from the right bank camshaft cover.

    13. Object Number: 945437 Size: SH
  13. Disconnect the barometric pressure (BARO) sensor electrical connector.

    14. Object Number: 945390 Size: SH
  14. Disconnect the intake manifold runner control solenoid electrical connector.
  15. Remove the left bank ignition coil wiring harness from the bracket.

    16. Object Number: 1391830 Size: SH

    Important: Do not remove the upper to lower intake manifold bolts.

    Important: DO NOT kink or damage the fuel pipe.

  16. Remove the intake manifold bolts.
  17. Reposition the intake manifold to gain access to the fuel pipe connector.

    18. Object Number: 1348200 Size: SH
  18. Remove the fuel feed pipe retainer.
  19. Disconnect the fuel feed pipe from the fuel rail. Refer to Metal Collar Quick Connect Fitting Service .
  20. Disassemble the intake manifold as necessary. Refer to Intake Manifold Disassemble .
  21. Clean and inspect the intake manifold and the sealing surfaces. Refer to Intake Manifold Cleaning and Inspection .

Installation Procedure

    Object Number: 902883 Size: SH
  1. Assemble the intake manifold as necessary. Refer to Intake Manifold Assemble .

    2. Important: Inspect and replace the lower intake manifold gasket only if the gasket is worn or damaged.

  2. Install the lower intake manifold gasket.

    3. Object Number: 1391830 Size: SH
  3. Install the intake manifold. Refer to Intake Manifold Installation .

    4. Object Number: 887871 Size: SH
  4. Connect the fuel injector harness electrical connector.

    5. Object Number: 945390 Size: SH
  5. Connect the intake manifold runner control solenoid electrical connector.

    6. Object Number: 945437 Size: SH
  6. Connect the BARO sensor electrical connector.
  7. Connect the PCV hose to the right bank camshaft cover.

    8. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1306504 Size: SH
  8. Install the upper intake manifold brace, bolt (2), and stud (1).

    9. Tighten
    Tighten the bolt/stud.

    8.1. Tighten the bolt (2) to 65 N·m (48 lb ft).
    8.2. Tighten the stud (1) to 10 N·m (89 lb in).

    Object Number: 1285256 Size: SH
  9. Install the wiring harness retainer.

    10. Object Number: 887881 Size: SH

    Notice: Ensure proper engagement of the wiring harness connector. The wiring harness connector must be installed straight onto the component connector and firmly seated. Visually inspect the connector to ensure that the connector latches are engaged and locked. Any damage to the connector or wiring must be repaired. Failure to follow this procedure can lead to an intermittent electrical connection, driveability concerns, and/or wiring harness or wiring harness connector damage or failure.

  10. Connect the throttle body electrical connector.

    11. Object Number: 887871 Size: SH
  11. Connect the fuel injector harness electrical connector.

    12. Object Number: 1348201 Size: SH
  12. Connect the fuel feed pipe (1) to the fuel rail. Refer to Metal Collar Quick Connect Fitting Service .
  13. Connect the purge line (3) to the purge solenoid valve.

    14. Object Number: 1348198 Size: SH
  14. Install the fuel pipe retainer.

    15. Object Number: 887878 Size: SH
  15. Connect the purge solenoid valve electrical connector.
  16. Install the brake booster hose and check valve to the brake booster.

    17. Object Number: 1305320 Size: SH
  17. Install the air inlet duct. Refer to Air Cleaner Inlet Duct Replacement .
  18. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement .