My Prius makes a very strange sound when one rear window is down

The fast you go, the faster the pulsations. And vice versa. This is strictly aerodynamics at work. When you open a window you create a big hole in the surface of what is essentially a surface that is designed to flow easily through the air. That hole creates turbulance because it "scoops" air into the vehicle, but the whole is not designed to smoothly scoop air into the vehicle and as such it creates turbulance and the pulsating sound.

 

ok- I noticed that you must try to balance the open windows on both sides of the car or things do get strange.....
it only makes sense with the areodynamics!
<div class='quotetop'>QUOTE(remaxmanager @ Apr 21 2006, 03:54 PM) [snapback]243301[/snapback]</div>