Whine or Growl Noise from the Power Steering System
WARNING: This page is about a different car, the 2003 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Whine Or Growl Noise From Power Steering System - Diagnostic Table (Steps 1 - 6)
Courtesy of GENERAL MOTORS CORP.
Fig 2: Whine Or Growl Noise From Power Steering System - Diagnostic Table (Steps 7 - 10)