'Fluttering'/soft rattle at speed
 

I've been noticing a slight sound coming from the right rear when I am traveling about 75-85 mph. It sounds like something is fluttering or a hard plastic rattling. I have looked all over the area and can't find anything loose. I may take the car in for the dealer to look at, but I'd love to hear if anyone has any ideas what may be causing it.

Can you reproduce the issue every time? Probably the first question theyll ask... If yes, tell them youd like to drive the car to show it to the tech, unless you want him breaking the law in your car for you.

could it be the back seat not shut all the way? or a seat belt in the back?

It's with the windows up, and yes, it happens every time.

After looking at the affected area, I think it might be the right rear flap in front of the tire. It is right from that area, but I don't have a good jack or lift access.

I have the exact noise of your description. I havent prodded around yet.

Very interesting. Let me know what you find out. :)

I have this noise as well in my FR-S. I haven't been able to figure out what it is. Anybody have any clue?

I have it too. Haven't figured it out yet.

Had this happen to me... Thought that the seat was locked and turned out it wasn't. The seat is unlocked if you see the red "pop-up" showing. My daughter had been sitting in the seat and I had not ever put the seat down; however, it was unlocked. I guess someone I showed the car to pull the release in the trunk.

Signs that I had were a constant low noise vibration coming from the back rear of the car. I noticed the raised "pop-up" yesterday and upon locking the seat back this fixed my issue.

Cool! I will check that out. :happy0180:

^I just figured it was a typical Subaru performance car... Squeaks and rattles usually don't bother me though (unless it was actually affecting the reliability and performance of the vehicle).

One thing I noticed on my BRZ was the license plate rattling when I shut my trunk. I used some 3M molding adhesive to stick the bottom of the plate down to stop it. If not stuck down it might rattle at speed.

I've heard a similar sound at speed. My first thought was that the sound was coming from the dash vents. It seemed to me that the intake for the cabin circulation system must be pointed forward and that air pressure at high speeds was causing the fans or diffusers to get overwhelmed and make noises in protest. I only hear the noise at 65-70+ mph, so it's definitely speed related.

EXACT same sound. Right rear, seemingly top of right seat or around there. Seat is up and locked. Happens every time at highway speed 70+. If I didnt know better I'd say it sounds like a trunk tension bar tapping on something - dont even know if our cars have trunk tension bars. Need to get back there and check it out with someone else driving.

just noticed this today, but it seems to happen more when I'm at WoT.... my buddy was in the car, we thought the sound was also coming from the top of the dash or in the vents as well.

We had the windows rolled up since I just washed the car and didn't want water to get all over the windows.... It was intriguing. It felt like vibration with air intake baffle thingy, idk it's weird thouoh... :iono:

could it be crankshaft or cams rattling?

no check engine light or anything though.

Skip to :54 in the video...is this what you are experiencing?



[ame="http://www.youtube.com/watch?v=rWZne5b2R3s"]Getting squirly in the FR-S - YouTube[/ame]

^^ Not the same thing. That noise and sensation in the video is chatter from extreme understeer.

I have metallic sound so maybe not the same problem - coming form right rear and I am pretty sure that it is seat lock problem (seat is locked).

I noticed I can make the slight rattling sound if I pound on the trunk mat on the right rear corner.
I can also make a rattling sound if I knock on the bottom diffuser part.
They may be one and the same and sounds like the thing I hear randomly when driving at freeway speeds.
Now, can someone figure out what exactly it is? I don't have a second person to help make the noise while I listen. Did not have time to go under the rear diffuser to see what's rattling inside that thing...

I can't see the vid posted since I'm at work, but I have the same issue. At first I thought it was just turbulent wind hitting the mirror then the body of the car, but it only happens on the right side.

Definitely only the right side for me, still happening. I'm going to take a look back there when it's on the lift at Injen next week.

I think I've got this too...spooky soft rattle sound from inside the dash at around or just over the speed limit. Seems only to happen under load though, not while coasting?

I've been experiencing this as well. Seems like it is something inside the car but I can't be certain. Happens with seat up or down, etc.

I've had this from day 1 in late May. I believe it was the rear wheel wells. If you go examine them, you'll see how loose they are. There are holes for the plastic snap screws to go into but it was never provided. I suspect that after 70mph, the plastic (loose) wells start chattering due to the wind. Go ahead and get some of those plastic clips/screws and look them into place. This might take care of it. Personally, I havent done it but I will tomorrow. I'll update on the results.

I believe in another post it was stated that those holes are pre-drills for mud guards... Be interesting to know if the clips does prevent this noise from occuring though!

Mine is definitely near the right rear wheel, even not under load.

I am also getting this, right rear at low highway speeds & above. Kind of a vibration, like something is loose and being buffeted by the increased airflow. Seems to be speed related and not just under acceleration. Haven't investigated it yet, got my BRZ a few days ago and wasn't able to take it out on the highway until today so I just noticed it. I'll post if I figure anything out. I have to go by the dealership Thursday so I'll ask them just in case they have some kind of idea or have had other complaints.

Right rear interior noise for me. In my case, the front passenger seat was all the way back pressed against the rear seat. I moved it forward a little so it did not touch and presto, the noise was gone.

I've had a bit of a rattle inside and my passengers have been NO help in tracking it down. I have only taken my FR-S on the highway one time for about two miles, have not had it above about 62 mph indicated (has only around 600ish miles now). The rattle happens at various speeds.

I'm pretty sure I'll just have to live with it. With all the road destruction going on these days around here, finding smooth pavement is rare.

One thing I did find early on was that the rear low mounted lighting assembly seemed fairly loose and rattly to the touch underneath the car, so I wedged in some adhesive damping pads. Not sure if that helped at all.

Same boat. Rattling sound *apparently* coming from the dash under WOT or heavy acceleration.

Doesn't seem to happen under mild acceleration or when revving with the clutch out.

Any clue what it is yet guys?

It's a pretty old thread but I thought I'd chime in. I had that flapping noise too. It only appeared at highway speeds at around 70mph cruising. It sounded like it was coming from the passenger side rear (perhaps near the wheel well). Turns out it was. It was the rear plastic covering for the wheel well. If you tap it you can hear it hitting the metal behind it. I just lifted it up a bit and put some double sided foam tape and the sound has gone away for now.......

I had the exact same issue, with the same fix. :thumbsup:

Take literally everything out of the car (all your personal things). Then try again. Rule out things in your coin tray / glove box / wherever first.

Say no more... are you sure no one has left an intentional "gap" in the exhaust....

Between my exhaust, radio and tire noise I don't think I would know if I had a soft rattle if there was one.

I think people have forgotten that the underbody panels flap a little . There's a spot where two panels are secured by 1 fastener over seas. In the US there is only 1 panel there and it creates a small gap due to the absence of the second panel that small space flaps up and down at speed. Stick a washer in it and you are good to go no rattle