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trunk vent rattle from sub question

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Old Apr 13, 2016 | 10:13 PM
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trunk vent rattle from sub question

So I was playing with my Subwoofer today and I always hear a rattling noise when I crank it up quite high coming from the trunk. I found the issues but I'm wondering if anyone has had the same problem and how they dealt with it?

the flap behind the fuse box in the trunk and I'm assuming there's one on the other side too but its covered.

any ideas on what i can do? I though about taping them open 24/7 or putting a foam piece just to hold it open bad ideas or no?
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Old May 8, 2016 | 02:32 PM
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I was worried about dust entering through flap if blocked open so I put fiberglass batting in front of vent. Vent still functions as intended and flapping noise is nominal.
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Old May 8, 2016 | 03:00 PM
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I can't quite envision that part but I just took care of an annoying instrument cluster rattle. I had the dealer try to fix it a few times but they were not successful. I found the issue was caused by the chrome colored rings around the gauges.

When I had everything apart I found this putty the dealer had used in trying to fix the problem. It was color matched to the trim. I removed the putty where they put it and I placed it at strategic points in the rings and then reassembled them. The annoying buzz is now gone.

Getting the rings off is a bit of a job which requires taking off a bit of the dash trim. A video on instrument cluster removal will get you there. Once the dash trim cover is off the rings can be easily pushed out but it's like a puzzle problem.

So something like this putty or felt tape might help.
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Old May 8, 2016 | 04:12 PM
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Originally Posted by michail71

So something like this putty or felt tape might help.
If the vent is the same as mine (sounds like it) then there is a flap which opens outward to equalize pressure such as when shutting trunk. The pressure from sub causes it to flutter creating slapping noise. Putting felt tape on flap MIGHT work but would be really hard to do (in my car at least the vent assembly is inserted from the body cavity in to trunk so would be a real PIA to remove and tweak).
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Old May 8, 2016 | 04:26 PM
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Originally Posted by MB Marko
So I was playing with my Subwoofer today and I always hear a rattling noise when I crank it up quite high coming from the trunk. I found the issues but I'm wondering if anyone has had the same problem and how they dealt with it?

the flap behind the fuse box in the trunk and I'm assuming there's one on the other side too but its covered.

any ideas on what i can do? I though about taping them open 24/7 or putting a foam piece just to hold it open bad ideas or no?
I wouldn't hold it open or closed. Those are designed to stay shut when you have negative pressure in the cabin, like using sunroof tilt, or open when you have positive pressure when setting to fresh air or closing the door as pointed out.

I like the fiberglass batting idea. Air can still go in and out while shutting out some of the flapping noises. Just don't impede the physical motion of the flap.
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Old May 8, 2016 | 06:26 PM
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Are you guys running stock subs and amps? I haven't noticed this yet and I've played some loud dubstep.
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Old May 8, 2016 | 10:23 PM
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holy i thought i would never get an answer to this, Im running a JL aftermarket sub and amp.

It' flutter like crazy I'm yet to solve this issue. I may try some of the ideas above, it was pretty loud on my way home for my weekend getaway.
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Old May 8, 2016 | 11:10 PM
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Oh yeah, I think you had the Audio 20 system. I haven't been able to drive the HK system to that level. But I'm getting older so I don't crank it up like I used too.

It sounds like those vents are doing their job anyway and you must be generating some good air pressure with that sub.
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Old May 9, 2016 | 03:36 PM
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ya audio 20, the EQu app and the aftermarket sub really bring the Audio 20 alive. The sub literally shakes the car its a small 10" in a low profile ported enclosure, so it takes up minimal trunk space. the vents are doing there jobs but its annoying listening to the clapping when it hits hard.

I really only crank it loud when I'm on the highway on long trips.
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Old May 9, 2016 | 11:40 PM
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The HK system is good but I don't think it would trigger that issue. It's balanced but lacks some of that deep punch.

I won't even listen to music in the stock config for the Audio 20. When I had my loaners I'd only listen to talk radio (they tend to have Audio 20 in loaners).

My old car would have issue with the interior door panels if the music got loud.
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