The sound is like that of a water pump whose bearing has gone bad. I have changed the water pump, idler pulley and the alternator. I used WD-40 to pin point the noise as it stops temporarilly when I spray the water pump pulley. I changed the water pump and it started again within a day. I am in the process of ordering a new belt tensioner, as it is spring loaded and I think it may be overloading the bearings. The sound is just anoying and beyond this next change I do not understand how I could fix this problem without dropping this car in an ARMY field artillery practice range!