Holy Crap. I had some papers on my passenger seat and it was nice enough to have the windows down instead of the AC on. I put the rear windows only down to circulate some fresh air into the cabin. All of a sudden my ears started to bleed(not really but can't be good for your hearing). The wind hitting the rear hatch from the inside creates a sound wave of base that will pop your left clavicle loose. Its deafening. Never had that happen to me in any other vehicle. It happens at say 40plus mph(not sure of speed since i was moving on main roads the few times i tried it...and it happened every time) Give it a try. I did a search and didn't see anything regarding this.

 

This is caused by the air not having anywhere to go.... happened in my VW New Beetle as well. The air flowing into the car comes in at a high speed and hits the flat rear hatch, causing the 'wumba-whooooommm' sound, and causing quite a bit of drag. One of the reasons I don't use the windows that much. That, and I live in Charlotte, where the air is anything but clean. =)

 

I have better results with lowering the front windows completely and then lowering the back windows an inch or so. You can also prevent the resonance by lowering the left and right windows differently.

I agree, it's a bother. I've never had a car with this problem before the xB.

Perhaps some wind deflectors on the front doors might make a difference.

George

 

exactly what i do! :D

 

Same here.....Also if you have a problem with the wind hitting your face while driving ( I do cause of my Contacts) lower your window and then the back window and it will work....

 

The problem is not unique to the Xb. It happens in all suv/van/wagon type vehicles. Sometimes it even happends in cars. If you would have cracked your front windows just a little bit, it most likely would have gone a way.

 

Here is a simple solution: What you have to do is get some pretty sizeable subwoofers, then hook a mike to the amp that picks up the sound of the wind vibration and plays it back out of phase. Now, you are going to have to play around a bit with speaker placement and getting the signal out of phase, but what I did is buy a noise cancelling pair of head phones and used them as a mike. Now I can have all my windows down, all the way, all the time. Give it a try.

 

I've had several small wagons, and they all do it. Enough air mass to easily compress it from the air rushing in as explained. 2 windows lowered a little fixes the problem as stated. The sound cancelling idea would be nice, I remember bmw ads or something talking about putting that into the headrests to eliminate tire and engine noise. "what are those huge subs for?" "I use them for silence!"

 

They need to just get rid of two switches and have a left side and a right side. Roll one down, the other goes with it. Better yet, design the rearmost side windows to vent open. That would be the best solution to the problem...

Think of it like water coming out of the tap and draining into a coke bottle. Once the bottle gets full, the water flowing in conflicts with the water being forced out. Same thing with the air when you have one window down.

 

I just vent the sunroof ;)

 

The same thing happened to me on a test drive. There were five of us going out a country road and the guy in the middle in the back seat had eaten onions and not taken a bath for a few days (true story). So me and the other outside guy got the idea at the same time for some fresh air and all of a sudden "whumpa-whumpa-whumpa" and even the seat belts started their own flapping.

The driver was in his own little world so he didn't really notice. We had to spray Glade air freshener inside the xB when they left and my dealership owner really laughed his rear end off over that one.

 

it is almost like a helicopter sound, but it pounds on the ears. i have noticed it all my cars i have owned and i have friends have it also. it depends on how the windows are rolled down and the speed you are driving. i usually do as george does when i have the front windows down i crack both of the rear windows.

 

you do know that the clavicle is located in the upper left anterior part of the chest right????

 

hehehe

 

its a joke.

i could have said it nearly popped my spleen....shook my taint...same effect

 

The problem is called ' buffeting ' it ia a areodynamic problem. It is not caused bu the rear hatch. It is a disruption of the air. Designers have the same problem with anything that will go through moving air. This includes planes, skyscrapers, aven bridges. Mechanical things care less about the sound but the vibrations can destroy what it is resonating. With only one window open you are basically turning your car into a big wistle.

Here is a quote from VW...
Varying levels of wind noise may occur with thepower roof open based on a number of factors,such as vehicle speed or the number ofwindows open. The aerodynamic shapes of a cars body design also play a role. As the car passes through the air efficiently, a disruption of the air flow over the body caused by a significant opening, like an open window or power roof, may cause a buffeting resonance, or wind noise, inside the vehicle. Wind noise can be minimized by changing the conditions that created the disruption. If conditions and comfort permit, reposition an open window, or open another window to change the buffeting resonance.

 

Yeah I hate when that happens. It is either crack all the windows or none at all.

 

It occurs to me that this may not be as much of a problem if you had vent shades. Can anyone with vent shades on their windows confirm or deny this?

 

The vent shades may change the aero dynamics of the car even still, which would explain why the sound isnt there with these insatlled.

What i have found to work ... roll down the rear window half way, then crack the fronts about an inch, then i get steady air circulation. Nothing stong enough to blow papers around. And i get same problem in my Neon, have since day one. so the rear hatch theory is out. :D