GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Riviera 🢒 Suspension 🢒 Automatic Level Control 🢒 Air Compressor Replacement

Removal Procedure
  1. Raise the vehicle and suitably support. Refer to Lifting and Jacking the Vehicle .

    2. Important: Before disconnecting the air hose from the intake air filter or the air compressor, clean the components and the surrounding area to prevent dirt and other foreign material from entering the ALC system.


    Object Number: 227996 Size: SH
  2. Disconnect the air tube from the air dryer.
  3. Remove the bolt and the harness tie with the air tube from the air compressor bracket.

    4. Object Number: 227988 Size: SH
  4. Remove the intake air filter from the vehicle.
  5. Remove the vehicle harness connector from the air compressor connector.
  6. Remove the two nuts, the bolt, and the air compressor assembly from the vehicle.

    7. Object Number: 227993 Size: SH
  7. Slide the air compressor connector off of the connector anchor.
  8. Remove two bolts and the heat shield from the air compressor bracket.

    9. Object Number: 227997 Size: SH
  9. Remove three bolts and the air compressor assembly from the bracket.
  10. Remove the air dryer from the air compressor. Refer to Automatic Level Control Air Dryer Replacement .

    11. Object Number: 226931 Size: SH
  11. Remove the air hose from the air compressor at two places.

    12. Object Number: 227985 Size: SH
  12. Remove the two screws and the two brackets from the air compressor.

Installation Procedure

    Object Number: 227985 Size: SH
  1. Install the two brackets on the air compressor with two screws.

    2. Tighten
    Tighten two screws to 7 N·m (62 lb in).


    Object Number: 226931 Size: SH
  2. Connect the air hose to the air compressor at two places.
  3. Install the air dryer on the air compressor. Refer to Automatic Level Control Air Dryer Replacement .

    4. Object Number: 227997 Size: SH
  4. Install the air compressor assembly onto the bracket with three bolts.

    5. Tighten
    Tighten three bolts to 3 N·m (26 lb in).


    Object Number: 227993 Size: SH
  5. Install the heat shield on the air compressor bracket with two bolts (Do not install the third heat shield bolt. It must be installed after the air tube is connected).

    6. Tighten
    Tighten two bolts to 4 N·m (35 lb in).

  6. Install the air compressor connector to the connector anchor.

    7. Object Number: 227988 Size: SH
  7. Install the air compressor assembly on the vehicle with two nuts and a bolt.

    8. Tighten

        • Tighten the bolt to 9 N·m (80 lb in).
        • Tighten two nuts to 9 N·m (80 lb in).
  8. Connect the harness connector to the air compressor connector.
  9. Install the intake air filter on the vehicle.

    10. Object Number: 227996 Size: SH
  10. Connect the air tube to the air dryer.
  11. Connect the air tube with the harness tie to the air compressor bracket with the bolt.

    12. Tighten
    Tighten the bolt to 4 N·m (35 lb in).

    Important: Before driving the vehicle, turn the ignition on and wait approximately 45 seconds. This will permit the ALC system to execute the ARC, ensuring that the air adjustable shock absorbers are filled with residual pressure.

  12. Lower the vehicle. Refer to Lifting and Jacking the Vehicle .