Have any of you had this problem?
When I'm driving down the interstate between 78 and 83. (which I normally cruise at 79, yes I know the speed limit is 70) I get a fluttering noise coming out the right rear (when I'm driving). The dealer said it was an exhaust moan and was not repairable. It would be something I have to live with. I just found this site this morning and wish I knew it was here along time ago. Any Ideas what this could be? It doesn't occur at any other speeds. So that eliminates most things. and the Diff checked out ok as well.

 

it might be a rear end whine. does it only happen under power, or all the time at a certain RPM, etc... the rear end whine is a high-pitched 'whirrr' when you're driving around 70 mph, and you can listen to it start and stop as you take your foot off the gas and then start to accelerate again. and do a search for more discussion; its come up before --

 

They originally said it was a rear end whine, but when I took it in to get it fixed they told me it was a noise coming from the exhaust. And yeah it only when the rpm is around 3,100 and as soon as you let off the gas it goes away. What I didn't understand and still don't if it was in the exhaust wouldn't replacing the exhaust fix it? And it's not really a high pitch as it more of a mild putter/flutter.

 

Do you get the fluttering with the windows up, down or both? With the windows down, I get a fluttering/buffeting of air in the rear compartment at speed. It doesn't happen with the windows up...obviously. Just something else to consider besides the exhaust.

 

I always leave the windows up, unless I'm trying to let the hot air escape before my AC kicks in. My other car is a firebird convertible so if I want some air I drive it. I probably ot to mention my car is an '05 limited coupe and I just hit 20,000 miles. If I didn't drive 80 miles a day, all interstate, all in the zone of the noise I wouldn't complain. I've never driven anything more fun to drive and I test drove the new vette before I bought my crossfire.

 

in the rear of the car in cargo area pull the access for your tail light passenger side and look in with flash lite down near the bottom you will see a black plastic square piece with a rubber flap on it. that lets air pressure out of the car when the windows are up. that is what is making your noise. there might be one on the other side also. i've thought of taking the rubber flap off. let me know if it works for you.

 

Danimal, the noise that he's describing, sounds to me like the "wind buffeting" sound that you mentioned, I too have noticed it when I drive with just my drivers window down. Usually all I do to make it go away is "crack" open the passenger window just a little bit.
But 13k9 mentioned it happens when his windows are up.
As Damian pointed out, it could be the "interior air exhaust flaps" opening and closing, or maybe they are blocked shut. But if that's true, where is all the massive amounts of air coming from that's building up in the interior.
13k9, try driving at your normal speed with the windows up, blower fan off, and set your ventilation system on recirculate. If you don't hear anything, then lower just your drivers window and see if you notice the sound that you mentioned. (You should be able to hear it even a lower speeds too). If that's the same noise that you described, then crack open the passenger window to make it stop.
I don't know what to tell you to do to stop it from happening when the windows are up, unless try Damians suggestion and open up the interior exhaust flaps. But I wouldn't remove them, maybe just block one open to see if that fixes the problem with the windows up. The only problem with blocking them open, is you may get carbon monoxide from your exhaust inside the interior.
If the fluttering sound goes away with the windows up, and recirculating on, and the fan off, but with the flaps blocked open, then your getting alot of air coming in from another location, and you shouldn't be. Good Luck.