Rear trunk area rattle from flapper box..What is it ? - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

22R · 12-16-2018, 11:34 AM

I have a slight rattle at idle RPM's so I investigated and I found it is coming from the passenger side back corner there is a black plastic box with some rubber flappers that vibrate like some kinda barometric equalizer or something ?? What is the name a purpose of this and is the one on the drivers side too ? Hurt anything to muffle em with a rag ??

Thanks,

22R

DarkPira7e · 12-16-2018, 11:55 AM

humfrz · 12-16-2018, 12:02 PM

Quote:

Originally Posted by 22R

I have a slight rattle at idle RPM's so I investigated and I found it is coming from the passenger side back corner there is a black plastic box with some rubber flappers that vibrate like some kinda barometric equalizer or something ?? What is the name a purpose of this and is the one on the drivers side too ? Hurt anything to muffle em with a rag ??

Thanks,

22R

Reference :

http://www.ft86club.com/forums/showthread.php?p=2452358

I understand they are there to allow some of the interior air out of the cabin when the doors are closed.

I reckon if they make a sound that bugs you, you could tape them open or shut -

humfrz

BirdTRD · 12-16-2018, 12:09 PM

They are Doggie doors....but for mice...don't ask me how I know.

22R · 12-16-2018, 12:11 PM

Quote:

Originally Posted by BirdTRD

They are Doggie doors....but for mice...don't ask me how I know.

That is them ! The rubber diaphragm vibrates at certain rpm's. I will just rubber band a microfiber towel over em to see if that helps.

Thanks,

22R

humfrz · 12-16-2018, 12:12 PM

Quote:

Originally Posted by DarkPira7e

Happy now?

humfrz

DarkPira7e · 12-16-2018, 12:37 PM

Yeah the boxes look like they're to keep the interior from being too sealed..Now I have to tear my car apart to find them!

bcj · 12-16-2018, 12:52 PM

They make it possible for the air handling system to move air through the fan and out the back.
You'd only get "Recirculation" otherwise.

soundman98 · 12-16-2018, 01:34 PM

jalopnik did a video on those a while back because it's quite a common question for an otherwise-obscure part:

https://jalopnik.com/heres-what-thos...-re-1828016409

8RZ · 12-17-2018, 08:23 AM

How else will your farts escape without those flaps?

soundman98 · 12-17-2018, 08:45 PM

i always assumed they were filtered through the passengers lungs.

HKz · 12-17-2018, 09:17 PM

damn, base exhaust must be quiet af

12-16-2018, 11:34 AM	#1
22R 22R Join Date: Apr 2017 Drives: 2012 Camry SE 2017 Toyota 86 Location: South Louisiana Posts: 233 Thanks: 234 Thanked 141 Times in 79 Posts Mentioned: 1 Post(s)	Rear trunk area rattle from flapper box..What is it ? I have a slight rattle at idle RPM's so I investigated and I found it is coming from the passenger side back corner there is a black plastic box with some rubber flappers that vibrate like some kinda barometric equalizer or something ?? What is the name a purpose of this and is the one on the drivers side too ? Hurt anything to muffle em with a rag ?? Thanks, 22R

12-16-2018, 01:34 PM	#9
soundman98 ProCrastinationConsultant Join Date: Sep 2013 Drives: '14 Ranger, '18 Tacoma 4Dr LB Location: chicago-ish Posts: 11,327 Thanks: 35,240 Thanked 13,676 Times in 6,782 Posts Mentioned: 98 Post(s)	jalopnik did a video on those a while back because it's quite a common question for an otherwise-obscure part: https://jalopnik.com/heres-what-thos...-re-1828016409 __________________ "The time you enjoy wasting is not wasted time"

12-17-2018, 08:45 PM	#11
soundman98 ProCrastinationConsultant Join Date: Sep 2013 Drives: '14 Ranger, '18 Tacoma 4Dr LB Location: chicago-ish Posts: 11,327 Thanks: 35,240 Thanked 13,676 Times in 6,782 Posts Mentioned: 98 Post(s)	i always assumed they were filtered through the passengers lungs. __________________ "The time you enjoy wasting is not wasted time"

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12-16-2018, 11:55 AM	#2
DarkPira7e Rust bucket enthusiast Join Date: Feb 2017 Drives: 2013 Turbo Firestorm FRS Location: Vermont Posts: 4,083 Thanks: 3,344 Thanked 4,234 Times in 2,129 Posts Mentioned: 33 Post(s)

12-16-2018, 12:37 PM	#7
DarkPira7e Rust bucket enthusiast Join Date: Feb 2017 Drives: 2013 Turbo Firestorm FRS Location: Vermont Posts: 4,083 Thanks: 3,344 Thanked 4,234 Times in 2,129 Posts Mentioned: 33 Post(s)	Yeah the boxes look like they're to keep the interior from being too sealed..Now I have to tear my car apart to find them!

12-17-2018, 09:17 PM	#12
HKz Reformed Join Date: Sep 2014 Drives: '23 GRC, '11 Prius, '04 RAV4 Location: Mesa, AZ Posts: 1,325 Thanks: 1,258 Thanked 1,152 Times in 596 Posts Mentioned: 8 Post(s)	damn, base exhaust must be quiet af

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