Using The Z4 As An Aquarium

[Sterling Roadster]

Hello folks!

Long story short I had to move the Z4 out of the garage for winter in February. Came back last week to check up on it and found that the passenger window has been down about 20 percent, likely since February. No idea how that happed as I did a couple walk arounds before I left it there, but maybe I missed that somehow.

I figure the next move will be removing the passenger seat and lifting the carpet to wet vac whatever sitting water is there. Any input would be appreciated, i've never removed the carpet from a car before so we will see how that goes. Also i'll try to take some photos of whatever ecosystem is living in there, for science purposes.

In any case, while the carpet feels dry i'm sure it's because all the water has made it down through the carpet and past the foam by now. The good news is that I understand a lot of wiring and connections run through there, and we know wiring and water go hand in hand. My question is, has anyone had to deal with something like this before on their Z?

[Phillies8008]

I wish I could give you some solid advice, but one thing I'd highly recommend is to use some mold killer on everything once you get the carpet up, because it's almost definitely present even if you can't see it.

Honestly, I'd be more apt to bring this to a professional detailer or maybe an upholstery shop. Better to have it done right than to live with a dank smell, or worse be breathing in potentially very harmful mold whenever you're driving it.

I don't think this would've made a big enough difference in your case, but FWIW whenever I know I'm not going to drive mine for a significant amount of time I put one of these in the cabin and the trunk to ward off any excess moisture. Especially during the Summer, which can be very humid where I live.

[Sterling Roadster]

Originally Posted by Phillies8008

I wish I could give you some solid advice, but one thing I'd highly recommend is to use some mold killer on everything once you get the carpet up, because it's almost definitely present even if you can't see it.

Honestly, I'd be more apt to bring this to a professional detailer or maybe an upholstery shop. Better to have it done right than to live with a dank smell, or worse be breathing in potentially very harmful mold whenever you're driving it.

I don't think this would've made a big enough difference in your case, but FWIW whenever I know I'm not going to drive mine for a significant amount of time I put one of these in the cabin and the trunk to ward off any excess moisture. Especially during the Summer, which can be very humid where I live.

I appreciate it. Still can't believe it happened at all but i'll have to start somewhere. I bought a dehumidifier but the cold weather prevents the moisture from rising for it to work in any case. The car has been stored indoors for the 11+ years i've had it so it's especially disappointing but i'm hoping the damage is reversible.

[Efthreeoh]

My E90 was flooded in May 2025 up above the headlights with organic-rich dirty river water. The interior flooded up to about 10 inches inside. Over the period of 6 weeks or so I wet-vac'd most all of the water out of the car and carpet. I then left the car in a place where the sun could get to the carpet with the doors and sunroof open. The interior completely dried out and there was no hint of mold.

Unfortunately, during the drying process, the fuel pump died, it was original with 426,000 miles on it, so not surprising, which helped make the decision to total the car and take the insurance payout. Meaning I did not have the car longer than July of 2025 to make any assessment of mold growth, but as of the day it was towed away in July, it had no mold.

I'd rent a small dehumidifier first before pulling the carpet.

[Huz-Z]

Fresh dry air and sunshine will work wonder. If you can park the car in the garage, can you put a fan nearby with the top down or windows open to circulate air through the cabin to help dry it?

[Sterling Roadster]

Originally Posted by Efthreeoh

My E90 was flooded in May 2025 up above the headlights with organic-rich dirty river water. The interior flooded up to about 10 inches inside. Over the period of 6 weeks or so I wet-vac'd most all of the water out of the car and carpet. I then left the car in a place where the sun could get to the carpet with the doors and sunroof open. The interior completely dried out and there was no hint of mold.

Unfortunately, during the drying process, the fuel pump died, it was original with 426,000 miles on it, so not surprising, which helped make the decision to total the car and take the insurance payout. Meaning I did not have the car longer than July of 2025 to make any assessment of mold growth, but as of the day it was towed away in July, it had no mold.

I'd rent a small dehumidifier first before pulling the carpet.

That's my worry with the car. Who knows what the damage could be, electrical gremlins are the worst. I've had the car for 11+ years and have about 300,000kms on it so there is not much value left in the car, nor does it really owe me anything. I've been eyeing 986 Boxster's, but every time I drive the Z4 I'm reminded I never want to let it go, so much fun. I'm hoping to remove most of the interior and use chemicals to prevent mold but we shall see what lies beneath.

[Sterling Roadster]

Originally Posted by Huz-Z

Fresh dry air and sunshine will work wonder. If you can park the car in the garage, can you put a fan nearby with the top down or windows open to circulate air through the cabin to help dry it?

This is the plan, problem is it's still quite cold here so the water just sits without evaporating. Hoping to have the carpets out with a dehumidifier and some chemical treatment.

[Huz-Z]

Originally Posted by Sterling Roadster

This is the plan, problem is it's still quite cold here so the water just sits without evaporating. Hoping to have the carpets out with a dehumidifier and some chemical treatment.

Maybe a big unit like this?

https://www.homedepot.ca/product/com...1213083#review

[Phillies8008]

I'd recommend treating for mold even if you don't think you see it. It can be embedded within the carpet fibers or foam cushioning (I assume the Z4 has this? Never pulled up the carpet.) making it difficult or impossible to see. At the very least it isn't going to hurt anything.

[Sterling Roadster]

Originally Posted by Huz-Z

Maybe a big unit like this?

https://www.homedepot.ca/product/com...1213083#review

Yup, one big a** fan will be in order!

[Sterling Roadster]

Originally Posted by Phillies8008

I'd recommend treating for mold even if you don't think you see it. It can be embedded within the carpet fibers or foam cushioning (I assume the Z4 has this? Never pulled up the carpet.) making it difficult or impossible to see. At the very least it isn't going to hurt anything.

I'll have to do this for sure. The thing about our cars is that the carpet is a thin layer on top of a thick layer of foam/insulation. The upper carpet portion dries to the touch on the surface but the foam underneath holds all the moisture. So the mold would be out of sight but likely growing happily.