The power steering fluid level is low.

1. Inspect for a power steering fluid leak. Refer to Power Steering Gear and Pump Leaks .
2. Add power steering fluid as needed. Refer to Checking and Adding Power Steering Fluid .

The pressure plates are scored.

Replace the power steering pump. Refer to Power Steering Pump Replacement .

The vanes are scored.

Replace the power steering pump. Refer to Power Steering Pump Replacement .

The pump bushing is scored.

Replace the power steering pump. Refer to Power Steering Pump Replacement .