2001 Dodge Intrepid 2001 Dodge Intrepid p/s noise

I have a 2001 intrepid with a 2.7 liter motor. When the car has sat overnite and I start it up the power steering makes a high whinning noise, then goes away after about 10 secs or so.I have replaced the idler pully, and p/s pump with a used one. It doesnt whine as long but problem is still there. Could it be bad p/s fluid. Help""""lol