Most Power Steering noise is caused by low fluid level. Check level in reservior. Other check is make sure belt is tight.
You might be low on power steering fluid
Possibly a worn belt on the power steering pumo.
check your power steering fluid
Power steering pump/fluid maybe
After bleeding the power steering the pump may make a noise because there isn't enough power steering fluid in it.
If the power steering pump is making a whiny noise on a Pontiac Grand Prix, the way to tell if this noise is from the pump or another source is to turn the steering wheel. If it turns hard, the problem might be with the pump. If the belt quiets down after a drop or two of dish soap is placed on the belt, then it was just the belt causing the noise.
first check power steering fluid,if to low then air is inside causing noise or p.s. pump is bad.
Noise may be heard in a power steering line when the power steering fluid is low. Low power steering fluid may occur due to a leaking power steering pump in most cases. If the pump is not leaking, then the fluid needs to be added.
If all the air isn't purged from the system, and if the fluid level is low, the pump will continue to make noise. Also, it may be that one of the idler bearings or accessory bearings are causing the noise, and not the steering pump.
If your power steering pump makes a whining noise as you turn your steering wheel your power steering fluid reservoir is probably empty. The noise is caused when your power steering pump tries to pump fluid that is not there. This indicates that you probably have a leak somewhere in your power steering fluid lines. You can either try to find the leak or simply replace the power steering fluid every so often.
check your power steering fluid
power steering fluid not filled?