On my wife's 98 4dr thier is a wierd humming noise coming from the back, she had been told me but I finally heard for myself yesterday while out with the family. When i turn the key you off course hear the pump kick in like regular but then when I turn the key completely then a different noise appears. It sort of sounds like a motor, but then while I had pulled over at a gas station just to hear the sound better I noticed that if I touch the power window switch the sound changed but only when I was applying the switch to open or close the windows. I am planning to look more into it this weekend when I am home, wondering and hoping if anyone has gone thru this and if so any help would be highly appreciated, thank you all.