# Mystery Square Hole Under Left Rear Fender Panel of Accord **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [January 26, 2017, 1:03am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047 "2017-01-26T01:03:22Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [January 26, 2017, 1:03am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/1 "2017-01-26T01:03:22Z")
There’s a wrecked Honda Accord in the local junkyard, a newer one, less than 10 years old I expect, got whacked on the driver’s side it appears, and I noticed there’s a weird square shaped hole, about 3 inches x 3 inches, under the left rear fender panel. The hole has a plastic box sticking through it. I was thinking it was just for a light fixture, but there’s no corresponding light fixture on the other side. So what’s the purpose of that hole? I’m thinking it has something to do w/the gas tank, right? But what? ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [January 26, 2017, 1:22am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/2 "2017-01-26T01:22:42Z")
No pic? No idea. ---
**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\ **Post date:** [January 26, 2017, 1:46am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/3 "2017-01-26T01:46:10Z")
I’d love a photo. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [January 26, 2017, 4:04am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/4 "2017-01-26T04:04:11Z")
When I say it is “under the panel” I mean that you’d have to remove the entire left rear fender panel to see it. There’s the real car, then there’s the part you see, that covers the real car. This hole is in the real car. Don’t have a photo or I’d post it. I expect one of the pro’s here who does body work has seen it many times and knows what it is for. ---
**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\ **Post date:** [January 26, 2017, 4:23am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/5 "2017-01-26T04:23:51Z")
You will see a lot of holes in the inner panels after removing a quarter panel. Is the “fender” missing or just the bumper cover? ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [January 26, 2017, 4:27am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/6 "2017-01-26T04:27:25Z")
Yes, the entire left rear fender is missing. ---
**Author:** ![wentwest](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/wentwest/32/6073_2.png) [@wentwest](https://community.cartalk.com/u/wentwest)\ **Post date:** [January 26, 2017, 4:35am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/7 "2017-01-26T04:35:57Z")
It’s probably an air vent, exhausts air that comes in through the cowl. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [January 26, 2017, 4:53am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/8 "2017-01-26T04:53:30Z")
That makes sense. You mean if the driver has the hvac controls so fresh air is coming into the passenger compartment , it has to go back out somewhere, and that’s one place it goes out? I can see that. I think on my Corolla it goes out under the doors, there’s some built in clearances at the bottom of the door jam for air to exit the passenger compartment, but maybe there are other places it goes out too. Like that one. ---
**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\ **Post date:** [January 26, 2017, 5:16am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/9 "2017-01-26T05:16:43Z")
The HVAC exhauster in attached to the quarter panel, remove the quarter panel and you will see into the trunk., no vents. ![](https://global.discourse-cdn.com/cartalk/original/2X/6/69af769c0d8e764c16971dbbdefe5e4c3c735c25.jpg) ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/48514_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [January 26, 2017, 1:37pm UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/10 "2017-01-26T13:37:27Z")
> [@wentwest](#): > > It’s probably an air vent, exhausts air that comes in through the cowl. That is exactly what it is. When positive air pressure is introduced into the cabin by activating the HVAC system, air is (passively) exhausted though that vent. If you were to see other models of cars–also sans rear quarter panel–you would observe the same thing on essentially all of them. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [January 27, 2017, 2:55am UTC](https://community.cartalk.com/t/mystery-square-hole-under-left-rear-fender-panel-of-accord/99047/11 "2017-01-27T02:55:36Z")
Yes, that’s where it is located and what it basically looks like, although the louvers were missing, probably damaged by the crash. The one I noticed was on the driver’s side, but there may have been on on the passenger side like the photo above, but that side wasn’t smashed so no way to see it. Good to know what it is for. Thanks. I’m curious about that panel above too. It seems like it is one piece that goes up and along the entire side of the roof up clean to the front of the passenger compartment. Is that a replaceable bolt on part or is is welded into and part of the car’s structure?