What's wrong with my P.S. pump? '02 SES

P.S. pump buzzing/humming noise varies depending upon whether accelerating, coasting, or decelerating. Sound is reminiscent of a dentist drilling my teeth. Is loudest while accelerating, hardly noticeable while coasting, and somewhat noisy decelerating.
Had one suggestion that the FWD torque placed on the steering rack causes the different noises.
Haven't been able to do anything to quiet it.
Any help appreciated.

Are you absolutely certain the noise is from the power steering pump and not the tensioner pulley or idler pulley? Does the noise vary if you turn the steering wheel when the car is at idle or does it only change based on engine speed? Have you checked the fluid level? Has any service recently been performed on the vehicle that may have introduced air in to the system, such as some service where the wheels may have been turned manually without the engine running?

-Rod

Noise is from the pump. Varies w/engine speed and pressure from accel or decell. Original started @ 106,000. Think I've exchanged some info about this w/you before. Car has had a lot done to it since those days, water pump, timing cover gasket, cam syncro - second time, master cylinder, valve rocker cover gaskets, belt tension wheel, etc, etc, etc. Changed the pump and fluid to 100% Mercon V and built myself a vacuum device to pull at the filler. Put the OEM pump back on it because was quieter than the junk "rebuilts" sold in parts stores. Ford service shows no interest in reclaiming some credibility by coming up with how to correct the Taurus pump noise. Now at 137,000 am about to make decision whether we want to listen to the buzzing/humming any longer. With all the Taurus' on the road, I couldn't possibly be the only one who is experiencing this - or could I ?
Thanks for the reply Rod.

Am posting again after driving 50,000 miles with this noise. As Rod questions, am not sure where the noise comes from. At 155,000 am about to throw in the towel on the vehicle but the way it looks and how comfortable and reliable it has been, want to keep it a couple more years.
i must be the only person who has had this problem.

I'm not sure you ever answered - Does the noise change when turning the steering wheel? Turning the steering at a stop would certainly load the pump more than any possible torque steer from the FWD. Is the noise present at idle with the car not moving? What if you rev the engine slightly with the car in Park or Neutral, does the noise appear?

-Rod