Today while driving I opened one back window. This created a huge wind pulsing inside the car. No other way for me to describe it. Almost like the pressure in the car was going up and down.

When I opened the one front window it went away. If I opened the sunroof only minimally went away.

Is this normal?

 

Yes, mine does the same. The sound is a little disorienting. So, I myself do not do this.

Not just on the acura, I travel a lot, and get rental cars all the time. This is what I experience in others. I generally just crack the front window, and crack the back...

 

Most cars do this.

Crack the sunroof open, it helps.

 

You're just building up the pressure in the car from only having a window open. To balance it out, open another window, to put it in simple terms. Nothing is wrong with your car.

Whenever I use the windows, my favorite combination is to have the driver, passenger and back right window opened equally (usually only 25% open). Creates a perfect flow IMO.

Here's actually a study about having one window open.

http://www.me.iitb.ac.in/~fmfp/FMFP%20PROC/am_13.pdf

 

I have never had a car do this. Not ever. I have come to find out that this is the reason:

The buffeting noise is from the airbag pressure response vents opening and closing. These vents are usually located at the rear of the car and keep your ear drums from being blown out if the airbags deployed when all the windows are up. So when you are driving with your windows down, the car fills with wind pressure, then the vents release, then repeat and so on.

 

p.s. most modern cars as early as 2000(maybe even earlier) have this pressure system in place.

weird that you've never come across this, what were you driving 1986 cars?

 

This issue actually came up long before airbags. Cars are designed aerodynamically these days. Opening a window/sunroof/whatever disrupts this airflow and allows ait to be trapped inside the car. Opening a window or closing the sunroof slightly either allows that air to escape or it changes the airflow into the car.

 

Hyundai Elantra
Mercury Marauder
Honda vtx 1300
Porche Panamera
Chrylser Concorde
Ford Sable
Mitsubishi Starion
Buick Century 350
Honda 250cc

I kid you not. Never have experienced it.

 

Something creates the severe pulsing and its not just wind coming in. Its got to be the airbag baffles. I suspect fit is also very good in the acura making the compartment very air tight. My previous cars are of a lesser build quality (except the Panamera).

Which I did not own...

 

BINGO. The Helmholz Resonance is the cause of the issue.

P.S. It has nothing to do with airbags or that mythical airbag pressure response vent built into the back of cars. Eric - would you mind telling us more about that?

 

All I can tell you is that I have been driving for 34 years and never had this issue.

The article I found said:

Helmholtz resonance finds application in internal combustion engines (see airbox), subwoofers and acoustics.

which would support something other than air alone causing the thumping.

Not so mythical: CLick Me

 

So in what cars has this patent been used in?

Airboxes, speakers and "acoustics" all involve the movement of air.

That noise you hear is air buffeting. It is a non-existent airbag flap opening and closing.

 

 

Does not matter, the point is its not a myth.

I do agree with you however, there is no air bag flap in the TSX, or likely in any other car.

Lets just stop here as you're beating a dead horse. Perhaps it is only air, but I think not. Especially considering I have never had this issue until the TSX which coincidentally has a subwoofer in the back of the car.