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For 1990-2009 cars only

Power Vacuum Brake Booster Replacement 3.8L

Tools Required

J 22805-B Power Brake Booster Holder

Removal Procedure

Caution: When replacing the power booster brake, make sure that the cruise control cable is not routed between the booster and the cowl. If the cable is damaged or pinched, it must be replaced. Failure to do this could result in personal injury.

  1. Remove the left instrument panel insulator.
  2. Disconnect the stop lamp switch electrical connector from the stop lamp switch.
  3. Remove the retaining clip and disconnect the brake booster pushrod from the brake pedal.
  4. Remove the cross vehicle brace. Refer to Cross Vehicle Brace Replacement in Body Front End.

  5. Object Number: 370383  Size: SH
  6. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
  7. Disconnect the brake fluid level sensor electrical connector from the brake fluid level sensor.
  8. Important: It is not necessary to disconnect the brake pipes from the master cylinder to the Brake Pressure Modulator Valve.

  9. Remove the two master cylinder retaining nuts and position the master cylinder aside.
  10. Disconnect the vacuum brake booster check valve from the brake booster. Position aside the vacuum hose and the check valve as an assembly.
  11. Disconnect the throttle and cruise control cables from the throttle body.
  12. Remove the throttle bracket, throttle cable, and the cruise control cable from the throttle body as an assembly. Position the throttle bracket and cables aside.
  13. Rotate the engine forward for service access. Refer to Rotating the Engine for Service Access in Engine Mechanical - 3.8L.

  14. Object Number: 190554  Size: SH
  15. Remove the EGR valve wiring harness heat shield.
  16. Remove the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 3.8L.
  17. Remove the transmission fluid filler tube bracket retainer and position the filler tube aside. Refer to Transmission Fluid Filler Tube Replacement .
  18. Attach the J 22805-B to the booster using the master cylinder retaining nuts.

  19. Object Number: 739251  Size: SH
  20. Unlock the booster from the front of the cowl.
  21. Use a flat bladed tool to depress the brake booster locking tab (1) out of the cowl mounting flange, while turning the booster counterclockwise with a ratchet on theJ 22805-B  (2).

  22. Remove the vacuum brake booster.

Installation Procedure

Notice: Internal components of this booster are not serviceable. The housing must not be unstaked and separated. Separating the housing will cause permanent deformation, preventing the booster from holding proper volume.

Notice: Inspect the locking flanges on booster and mounting plate. Replace the booster and mounting plate if the locking flanges are bent or damaged.

  1. Install the vacuum brake booster.
  2. Position the vacuum brake booster on the cowl counterclockwise from the final installation position so that the locking flanges on the vacuum brake booster and on the cowl mounting flange engage.

    Important: Ensure that the locking tab and the flanges are in the fully engaged position.


    Object Number: 739251  Size: SH
  3. Turn the vacuum brake booster clockwise with a ratchet on the J 22805-B  (2). DO NOT use a flat bladed tool in the locking tab to install the vacuum brake booster. When the vacuum brake booster is correctly installed, the locking tab (1) slides up the flange and engages the locking notch.
  4. Remove the J 22805-B  (2) from the installed vacuum brake booster.
  5. Install the transmission fluid filler tube bracket retainer and reposition the filler tube. Refer to Transmission Fluid Filler Tube Replacement .
  6. Install the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 3.8L.

  7. Object Number: 190554  Size: SH

    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.

  8. Install the EGR valve wiring harness heat shield.
  9. Tighten
    Tighten the EGR valve wiring harness heat shield nut and bolt to 10 N·m (89 lb in).

  10. Return the engine to the original rest position. Install the left and right engine mount struts. Refer to Engine Mount Strut Replacement - Left Side and Engine Mount Strut Replacement - Right Side in Engine Mechanical - 3.8L.
  11. Reposition the throttle bracket and cables to the throttle body. Install the throttle bracket, throttle cable, and the cruise control cable assembly to the throttle body .
  12. Connect the throttle and cruise control cables to the throttle body.
  13. Reposition and connect the vacuum hose and check valve assembly to the booster.

  14. Object Number: 748291  Size: SH
  15. Reposition the master cylinder onto the booster and install the master cylinder retaining nuts.
  16. Tighten
    Tighten the nuts to 25 N·m (18 lb ft).

  17. Connect the brake fluid level sensor electrical connector to the brake fluid level sensor.

  18. Object Number: 370383  Size: SH
  19. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
  20. Install the cross vehicle brace. Refer to Cross Vehicle Brace Replacement in Body Front End.
  21. Connect the brake booster pushrod to the brake pedal and install the retaining clip.
  22. Connect the stop lamp switch electrical connector to the stop lamp switch.
  23. Install the left instrument panel insulator.

Power Vacuum Brake Booster Replacement 3.4L

Tools Required

J 22805-B Power Brake Booster Holder

Removal Procedure

Caution: When replacing the power booster brake, make sure that the cruise control cable is not routed between the booster and the cowl. If the cable is damaged or pinched, it must be replaced. Failure to do this could result in personal injury.

  1. Remove the left instrument panel insulator. Refer to Instrument Panel Insulator Replacement in Instrument Panel, Gauges, and Console.
  2. Disconnect the stoplamp switch electrical connector from the stoplamp switch.
  3. Remove the retaining clip and disconnect the brake booster pushrod from the brake pedal.
  4. Partially drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  5. Remove the cross vehicle brace. Refer to Cross Vehicle Brace Replacement in Body Front End.
  6. Remove the air cleaner inlet duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls-3.4L.
  7. Relieve the fuel system pressure. Refer to Fuel Pressure Relief in Engine Controls-3.4L.
  8. Disconnect the EVAP canister purge valve pipe, the fuel feed pipe and return pipe. Position them aside.

  9. Object Number: 466875  Size: SH
  10. Disconnect the coolant outlet (2) and inlet (3) bypass hoses and position them aside.
  11. Remove the heater inlet pipe.
  12. Rotate the engine forward for service access. Refer to Rotating the Engine for Service Access in Engine Mechanical - 3.4L.
  13. Disconnect the brake fluid level sensor electrical connector from the brake fluid level sensor.

  14. Object Number: 748291  Size: SH

    Important: It is not necessary to disconnect the brake pipes from the master cylinder to the BPMV.

  15. Remove the two master cylinder retaining nuts and position the master cylinder aside.
  16. Disconnect the vacuum brake booster check valve from the brake booster. Position aside the vacuum hose with the check valve as an assembly.
  17. Attach the J 22805-B to the booster using the master cylinder retaining nuts.

  18. Object Number: 739251  Size: SH
  19. Unlock the booster from the cowl.
  20. Use a flat bladed tool to depress the brake booster locking tab (1) out of the cowl mounting flange, while turning the booster counterclockwise with a ratchet on the J 22805-B  (2).
  21. Remove the vacuum brake booster.

Installation Procedure

Notice: Internal components of this booster are not serviceable. The housing must not be unstaked and separated. Separating the housing will cause permanent deformation, preventing the booster from holding proper volume.

Notice: Inspect the locking flanges on booster and mounting plate. Replace the booster and mounting plate if the locking flanges are bent or damaged.

    Important: Carefully push the pushrod eye through the hole so that you do not damage or dislodge the insulator boot.

  1. Install the vacuum brake booster.
  2. Position the vacuum brake booster on the cowl counterclockwise from the final installation position so that the locking flanges on the vacuum brake booster and on the cowl mounting flange engage.

    Important: Ensure that the locking tab and the flanges are in the full engaged position.


    Object Number: 739251  Size: SH
  3. Turn the vacuum brake booster clockwise with a ratchet on the J 22805-B  (2). DO NOT use a flat bladed tool in the locking tab to install the vacuum brake booster. When the vacuum brake booster is correctly installed, the locking tab (1) slides up the flange and engages the locking notch.
  4. Remove the J 22805-B  (2) from the installed vacuum brake booster.
  5. Reposition and connect the vacuum hose and check valve assembly to the booster.

  6. Object Number: 748291  Size: SH

    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.

  7. Reposition the master cylinder onto the booster and install the master cylinder retaining nuts.
  8. Tighten
    Tighten the master cylinder retaining nuts to 25 N·m (18 lb ft).

  9. Connect the brake fluid level sensor electrical connector to the brake fluid level sensor.
  10. Return the engine to the original rest position. Install the left and right engine mount struts. Refer to Engine Mount Strut Replacement - Left Side and Engine Mount Strut Replacement - Right Side in Engine Mechanical - 3.4L.
  11. Install the heater inlet pipe.

  12. Object Number: 466875  Size: SH
  13. Reposition and connect the coolant outlet (2) and inlet (3) bypass hoses.
  14. Reposition and connect the EVAP canister purge valve pipe, the fuel feed pipe and return pipe.
  15. Install the air cleaner inlet duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls-3.4L.
  16. Install the cross vehicle brace. Refer to Cross Vehicle Brace Replacement in Body Front End.
  17. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  18. Connect the brake booster pushrod to the brake pedal and install the retaining clip.
  19. Connect the stoplamp switch electrical connector to the stoplamp switch.
  20. Install the left instrument panel insulator. Refer to Instrument Panel Insulator Replacement in Instrument Panel, Gauges, and Console.