Power steering belt or the power steering pump.
This is two of the things I know that could be wrong. The power steering pump is either bad or there is no power steering fluid in the pump causing it to have steering problems. Be sure to check the fluid level in the power steering pump.
The power steering on a vehicle can be jammed due to a rack and pinion issue in the steering column. Another possible cause could be that the power steering fluid may be low and the power steering pump may be going out.
It is not possible to alter a car from a manual steering into a power steering car. The engines for the two types of cars are very different.
power steering pump failure ----------------------- If it is a Dodge truck then i see alot of Power steering pump shafts that are broken. To test, then pull on the power steering pump pulley - if it pulls out then you have a broken pump shaft.
form_title= Power Steering Oil form_header= Steer with ease when you refile your power steering. When was the last time you checked the steering oil?*= _  What was the last time the steering oil was changed? *= _  Do you have any problems with your power steering?*= () Yes () No What steering oil do you normally use?*= _ 
there is no power steering fluid, this is an electric assist power steering system, is you are having problems let the experts handle this go to the dealership.
It is not possible to remove the power steering pulley on a 1997 Buick Le Sabre without removing the power steering pump.
More than likely... the power steering belt.
Whining noises often come from the alternator or the steering pump. Check the power steering fluid in the pump (there is a dipstick on the pump), and have an AVR test done on the alternator. If the alternator is faulty, you are probably having battery problems as well. If the steering pump is low on fluid or is faulty, you probably are experiencing jerky steering from time to time.
Could be the power steering pump is failing or low on fluid.