Causes of power steering noise include low steering fluid level, dirty or old power steering fluid, a drive belt problem, and issues with the power steering pump. Different types of power steering problems produce different sounds, and other sounds may mimic the sound of a power steering issue.
The main cause of power steering noise is low power steering fluid level. The sound may be a whining sound that occurs upon turning the steering wheel. The power steering pump requires hydraulic fluid to aid in steering. The car should have a dipstick to check the power steering fluid level. The fluid can also become dirty; it sometimes needs to be purged and replaced.
If the sound is a higher-pitched wailing sound, the problem may be the that the power steering pump drive belt has slipped or is loose. If the sound is a screeching sound, the problem may be the power steering pump itself. The power steering pump normally is very long lasting, but it can wear out over time, especially when the fluid is dirty. The bolts on front-suspension struts can also cause a sound much like a power steering issue, and this also occurs only when turning the wheel.