I did a search and found a few people that mentioned hearing it but no solutions or target areas so I'd like to provide more details on the exact sound and it's whereabouts. First, it sounds like it's coming from the passengers side foot area. The fluttering becomes more noticable when I climb above 4k RPMS. I would describe the fluttering sound like a plastic bag being flicked with your finger repeatedly; "the higher the RPMS the faster the flicks". (LOL If that makes any sense!) Not sure if this is normal or not but I just barely noticed it since I've owned the car for a month and half and usually I have my music turned up.

Just curious to know if anyone else experiences this and what was done to eliminate the noise and whether its something serious.

Thanks!

 

only thing I can think of is an exhaust leak. Check all your bolts from the exhaust manifold on back.

 

I'll check the exhaust.

Anyone else? Am I being just a little too observant?

 

You probably are. When I first got my S I was paranoid about every little sound. Fluttering, squeeks, etc etc. More often than enough, you are fine. Unless you hear your diff clunking, or something else significantly loud, you are most likely good to go. If you are really worried, have a leakdown and compression test and have a once over done on your car.

 

Something in the climate control system vents?

 

My daily beater, a '92 Acura Legend, makes this noise. Its HVAC related in my case - turn the fan up, the flutter gets faster - reminds me of the cards in the bicycle spokes sound. Sometimes it does it, sometimes it doesn't. Whatever.

Turn your HVAC off and see if it goes away. Thats my contribution.

 

sounds like what I have. It's the throttle body making that noise. Something about how the abnormal flow of the air, blah blah blah.

There is a thread about it that I posted. It's sort of a metal high pitch sound that flutters around 3.5 to 4k rpm, right only when you're on the throttle?

 

You may want to check that right away, I just pulled and replaced the blower unit in my wifes Accord that was making a sound similar to this, got worse as you upped the speed all that.

Well, a few months prior, she had this problem with a mouse in her trunk but it had suddenly vanished right around the same time this sound from the heater started.

Pulled the blower and there was the mouse, rather dehydrated and feet sticking out of the fins...

I can only imagine the bacteria that thing was blowing in the cabin.