Power-steering pumps can develop big leaks or fail from general wear and tear. Several warning symptoms can occur ahead of time to let you know there's a problem with the pump. It may be something simple like low fluid level or a leaky hose. Changes in function or unusual noises are the main signs something might be wrong.
Squealing While Turning
A squealing sound while turning, particularly at tight corners or while driving slowly, is a symptom of a bad power-steering pump.
Squealing at Start-Up
A squealing or chattering noise from under the hood when the car is first started may indicate problems with the power-steering pump.
Stiff steering in cold weather or while turning at low speeds is a symptom of a bad power-steering pump.
Erratic functioning, such as a bit of slippage while turning the wheel, can indicate a bad power-steering pump.
Lack of Power
Power steering that seems to go out for a second during slow turns is a symptom of a failing power-steering pump.