Stuck or inoperative flow control valve

Replace or clean the valve.

Pressure plate is not flat against the cam ring

Replace the pressure plate.

A scored pressure plate, thrust plate, or rotor

1. Replace any scored parts.
2. Refer to the appropriate procedure:
3. Power Steering Pump Disassemble
4. Flush the system
5. Refer to Power Steering System Flushing

The vanes are sticking in the rotor slots.

Free the vanes by removing any burrs, varnish or dirt.

Improper installation of the vanes

Properly install the vanes. Ensure that the radius edge is installed to the outside.

Air in the fluid

Locate and repair the leak.

Low power steering fluid

Add the necessary amount of power steering fluid.

The pump belt is slipping.

Refer to Drive Belt Replacement or Drive Belt Replacement in Engine Mechanical.

Damaged hoses or steering gear

Replace any damaged parts.