About a month ago I went up to TN for a show and it was raining (not too heavily) for most of the way there (4 hr drive). Later that day I wound up taking off the backseat while troubleshooting some audio problem - I have wires running under the rear seat - and I found my ENTIRE rear seat underneath the cloth seat was flooded with standing water. It soaked through a good part of the factory foam under the seat. There was no leak coming from the headliner, it all came from below somewhere. I noticed there's a 1/2" factory hole in the chassis about a foot below the floor of the seat that you can see when you remove the seat clips, but the backseat was clipped on the entire time, blocking the hole. I am still stumped as to how a full 1/4" of standing water wound up underneath my seat that's sitting a good 2ft or so above the ground at all times. I have no idea how long that's been happening but I am afraid it will eventually rot out the metal.

Where the bloody heck is this coming from, and has this happened to anyone else? AFAIK I haven't been driving through any lakes...

 

Rear windows, rear side windows?

 

How would that cause a huge flood only under the seat? The sides of the seat weren't wet. It was just entirely from beneath it.

I'm not kidding when I say it was flooded. There was literally standing water across the whole thing. Large amounts of water. Like someone dumped a coke bottle's worth of water.

 

If u have a sunroof it can be one of the vent tubes leaking, or windows, if it happens again look at your rear side interior panels if there's marks that look like water ran down em than the leak is up high

 

No sunroof. The side and rear windows appear to be normal. Next time it rains I will go in there and poke around a bit. But I just can't get past how much freaking water was in there, you'd think it would be obvious if the windows were leaking THAT much... no? I really don't know, has anyone else experienced this?

 

I am wondering if it is not coming in from the cabin air filter area . Have you done that mod yet ??
https://montecarloforum.com/forum/si...lem-fix-26663/

 

Honestly its sometimes hard to tell if a window is leaking especially when there covered up, I had a water leak like that but my roof came unglued in one spot

 

Just becuase the seat was not wet does not mean it wasn't a window, my 4th gen kept getting puddles under the rear seat, only noticed it becuase i was doing a deep cleaning and pulled the rear seat, the rear window was leaking and it traveled behind the seat down