Purging Power Steering System of Air

A whining noise heard from the power steering pump may be caused by air in the system.

The following "purge the power steering system of air" service procedure must be performed whenever any of the following services are performed:

• All power steering noise complaints with evidence of aerated fluid on pre-delivery vehicles only, prior to any component service.
• Any power steering system component (gear, hose, etc).

  NOTE: If the air is not purged from the power steering system correctly, a second customer concern or pump failure could result. This condition can only occur on pre-delivery vehicles with evidence of aerated fluid or vehicles that have had steering component service.

Fluid Level Top-Off Procedure

1. Check and fill pump reservoir to dipstick full cold or remote reservoir center mark.

2. Disable ignition by disconnecting the EDIS/DIS/TFI module or for remote TFI disconnect CMP/HALL EFFECT/PIP SENSOR. Shutoff solenoid (on the injection pump) must be disconnected to prevent starting.

3. Crank engine 30 seconds, check fluid level and add if required.

4. Crank engine 30 seconds while cycling lock to lock.

   NOTE: Do not hold steering wheel on stops.

5. Check fluid level and add fluid if required.

Air Purge With Vacuum External Source Procedure

1. Tightly insert the rubber stopper of the air evacuator assembly into pump reservoir.

2. Reconnect connection used to disable ignition. Start vehicle.

3. Apply 20-25 in-Hg (68-85 kPa) maximum vacuum for minimum of three minutes at idle; maintain maximum vacuum with vacuum source.

4. Release vacuum and remove vacuum source.

5. Add fluid to full warm or reservoir center mark.

6. Reinstall vacuum source and apply 20-25 in-Hg (68-85 kPa) vacuum.

7. Cycle steering wheel from lock to lock every 30 seconds for approximately five minutes.

   NOTE: Do not hold steering wheel on stops.

8. Shut engine off, release vacuum, remove vacuum source and lower front end.

9. Add fluid if necessary, install dipstick or reservoir cap.

10. Start engine and cycle steering wheel from lock to lock every 30 seconds for approximately five minutes.

    NOTE: Do not hold steering wheel on stops.

11. Check for oil leaks at all connections.

    NOTE: In severe cases it may be necessary to repeat air purge with vacuum source procedure.