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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

  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  2. Remove the left instrument panel insulator. Refer to Instrument Panel Insulator Panel Replacement - Left Side in Instrument Panel, Gages, and Console.
  3. Remove the retaining clip and disconnect the brake booster pushrod from the brake pedal.

  4. Object Number: 370383  Size: SH
  5. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
  6. Disconnect the brake fluid level sensor electrical connector from the brake fluid level sensor.
  7. Important: It is not necessary to disconnect the brake pipes from the master cylinder to the brake pressure modulator valve (BPMV).

  8. Remove the 2  master cylinder retaining nuts and position the master cylinder aside.
  9. Disconnect the vacuum brake booster check valve from the brake booster. Position aside the vacuum hose and the check valve as an assembly.
  10. Rotate the engine forward for service access. Refer to Rotating the Engine for Service Access in Engine Mechanical - 3.8L.

  11. Object Number: 190554  Size: SH
  12. Remove the EGR valve wiring harness heat shield.
  13. Remove the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 3.8L.
  14. Remove the transmission fluid filler tube bracket retainer and position the filler tube aside. Refer to Transmission Fluid Filler Tube Replacement in Automatic Transaxle - 4T65-E.
  15. Remove the BPMV. Refer to Brake Pressure Modulator Valve Bracket Replacement in Antilock Brake System.
  16. Attach the J 22805-B to the booster using the master cylinder retaining nuts.

  17. Object Number: 739251  Size: SH
  18. Unlock the booster from the front of the cowl.
  19. 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).

  20. Remove the vacuum brake booster.
  21. Remove the J 22805-B  (2) from the 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 BPMV. Refer to Brake Pressure Modulator Valve Bracket Replacement in Antilock Brake System.
  6. Install the transmission fluid filler tube bracket retainer and reposition the filler tube. Refer to Transmission Fluid Filler Tube Replacement in Automatic Transaxle - 4T65-E.
  7. Install the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 3.8L.
  8. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 190554  Size: SH
  9. Install the EGR valve wiring harness heat shield.
  10. Tighten
    Tighten the EGR valve wiring harness heat shield nut and bolt to 10 N·m (89 lb in).

  11. 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.
  12. Reposition and connect the vacuum hose and check valve assembly to the booster.

  13. Object Number: 748291  Size: SH
  14. Reposition the master cylinder onto the booster and install the master cylinder retaining nuts.
  15. Tighten
    Tighten the master cylinder retaining nuts to 33 N·m (24 lb ft).

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

  17. Object Number: 370383  Size: SH
  18. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
  19. Connect the brake booster pushrod to the brake pedal and install the retaining clip.
  20. Install the left instrument panel insulator.
  21. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.

Power Vacuum Brake Booster Replacement LY7

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. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  2. Remove the left instrument panel insulator. Refer to Instrument Panel Insulator Panel Replacement - Left Side in Instrument Panel, Gages and Console.
  3. Remove the brake apply sensor (BAS).
  4. Remove the retaining clip and disconnect the brake booster pushrod from the brake pedal.
  5. Remove the exhaust system crossover pipe. Refer to Exhaust Crossover Pipe Replacement .
  6. Disconnect the brake fluid level sensor electrical connector from the brake fluid level sensor.
  7. Remove the antilock brake system (ABS) module bracket fasteners from the left front fender.
  8. Remove the ABS module bracket.
  9. Remove the master cylinder mounting nuts and separate the master cylinder from the vacuum brake booster and position aside.
  10. Important: It is not necessary to disconnect the brake hydraulic pipes from the master cylinder or brake pressure modulator valve.

  11. Disconnect the vacuum brake booster check valve from the brake booster. Position aside the vacuum hose and the check valve as an assembly.
  12. Drain the cooling system. Refer to Cooling System Draining and Filling .
  13. Remove the coolant heater pipes from the engine.
  14. Attach the J 22805-B to the booster using the master cylinder retaining nuts.

  15. Object Number: 739251  Size: SH
  16. Unlock the booster from the front of the cowl.
  17. 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).

  18. Remove the vacuum brake booster.
  19. Remove the J 22805-B  (2) from the 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. Reinstall the coolant heater pipes.
  6. Reposition and connect the vacuum hose and check valve assembly to the booster.
  7. Notice: Refer to Fastener Notice in the Preface section.

  8. Reposition the master cylinder onto the booster and install the master cylinder retaining nuts.
  9. Tighten
    Tighten the master cylinder retaining nuts to 33 N·m (24 lb ft).

  10. Reinstall the ABS module bracket and fasteners.
  11. Tighten
    Tighten the ABS module bracket nuts to 10 N·m (7 lb ft).

  12. Connect the brake fluid level sensor electrical connector to the brake fluid level sensor.
  13. Reinstall the exhaust system crossover pipe. Refer to Exhaust Crossover Pipe Replacement .
  14. Refill the cooling system. Refer to Cooling System Draining and Filling .
  15. Connect the brake booster pushrod to the brake pedal and install the retaining clip.
  16. Reinstall the BAS.
  17. Tighten
    Tighten the BAS bolt to 2.5 N·m (22 lb in).

  18. Install the left instrument panel insulator.
  19. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.