Freakin' smell when wot.. Solved..
 

I don't know if a solution has beem found for that sulfur smell when you go WOT.. Unless some one pulls your finger while driving.. But i think i found a solution.. I tried google but found nothing.. Most suggested a change in fuel or change the cabin filter.. None of which worked.. Anyway this is what i found.. Hope it helps..

You need to tape up the flap that is found on each end rear side of your car.. This thing is very close to the exhaust which suggest fumes coming in from there..


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You can move the wires to gain better access

This is what you need to remove


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Freaking flap is almost gone


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Cover it with tape.. Color doesn't matter since it wont be seen anyway.. Also make sure to give a little extra on each end of the tape to go past the corners.. It will serve as an extra hold since it will be between the flap device and the body frame..


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Inside..<br/>


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And outside.. Again dont worry about the color of tape you use.. Nobody can see it

Here it is back after tape install


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I should point out that the drivers side is easy to remove since there is enough space.. Just push the two clips that hold it, push the thing out little bit and pull it back in or you can just push the whole thing and it will drop on the side of the fender.. The passenger side is a little bit tricky since the amp is blocking the way.. To reinstall just push it back from outside the body frame.. There is enough space to work with but you will be lying on the ground.. Anyway did a quick run and PRESTO! No more freaking fart smell.. I figured the smell has to come from somewhere and that is the only thing i can think off... I don't think it comes from the front since most of the smell comes fron the rear.. YMMV.. Good luck

Also that damn click sound you hear when you close your rear doors will be gone as well

Wow is this really the solution?? You can't smell the gas at all?

-Josh

Those are the cabin pressure release valves. Will this affect anything if sealed off completely?

Those are there for a reason, I wouldn't close them up.

I would agree, better solution is to go to PPE/ Sikky headers and enjoy the extra power!

I thought the smell was because of the cats........meow

I'm not sure if anyone here saw the thread on the sunroof glass blowing out, but it has happened. Imagine it's quite a hot day any you're parked outside. As the air inside the cabin heats up and expands it has nowhere to go because you blocked the vents. Something's gotta give.

honestly, that would be fun to see as long as it wasn't mine

Your flaps were all kinds of jacked up lol. I need to check mine. I'm thinking its best to replace them and use some sort of spring that will keep the flap closed tight and only open when cabin pressure is excessive.

When i was getting my windshield replaced I mentioned to the "glass pro" that I was surprised the cracks didn't spider web across the windshield like I have seen happen many years ago. He mentioned new cars have flaps that prevent pressure from building up in the cabin.
Now I know where the flaps are located. Good info to know.
I also have noticed that smell. Now that my F is "catless" there is a stronger exhaust smell on the inside sometimes. I may just put some fabric over the flaps to still allow air to escape under pressure but prevent exhaust smell from coming in so easily.
I would rather have the Lexus smell than exhaust smell. I like the Lexus smell. I need "new lexus smell" air freshener!

I googled trunk flap vents.. One use for them is to release some pressure when closing your doors and trunk.. But how much pressure are we really talking about here.. I dont think sealing them and closing your doors will break your windows / sunroof... I work in aviation and you need a tremendous difference in pressure in and out to get depressurization and blow your windows out.. Granted it's different since you are squeezing the air inside the cabin when you close the doors and trunk but the volume is not that great.. Also our cabin is not completely sealed.. Ever notice air coming in even though you have everything closed when u drive, mostly coming from the firewall and side doors.. If air is coming in, they have a way of coming out.. I also found out that some that do close those vents do so because of aftermarket subwoofers installed .. They seal them to stop the rattle.. I'm not saying for you to go out and do this but if this is the only solution to stop the fume smell for now then i'm all for it.. Yes, they are there for a reason but so are catalytic converters which some remove to get better exhaust airflow.. The smell is not coming from the firewall unless you have a crack in your manifold or under your flooring either.. It is coming from the rear and that flap is the only culprit i see, right next to the exhaust.. I sat inside the car and opened closed each door front and back and i felt no change in pressure ( maybe becuase i'm so used to it).. Again ymmv...

Also our exhaust tip does not go past the bumper which means that most fumes are trap within there.. I'm sure anyone who went aftermarket exhaust where the tips extending beyond the bumper does not have this problem anymore

I don't think the car is sealed enough. The vents in ventilation system would have to be 100% tight to build pressure inside the car. Even inside doors there is plastics that act like vapor barrier, these would also need to be 100% sealed....

These vents on the back are for large air movement and probably it's harder to close the doors without them.