So I'm 99% sure it was the seal issue in the linked video above, but I never actually did anything about it. It ended up going away on its own after a few weeks, not sure if a seal ended up forming a proper shape in the heat of the summer or what.

 

that was probably it , if that gutter in the door trim was collecting water after a rain , it was leaking past the plastic sheet behind the door panel . the panel itself is just a cover , it won't stop
any water that gathers behind it . on my front right door it was leaking past bottom of the speaker mount . resealed it and the problem never came back

 

I love how the youtube vid was made in the rain. gives it extra "character"

 

Hello, I have 2018 Fit Sport. Picked it up at the end of November and noticed condensation on the inside of the car as the temps got colder. Pulled up the rubber floor mats and found the floor in the back seats to be damp. During the last rain, I put towels down on the floor of each seat to see where it is coming in. To my surprise, the only dry towel was on the front passenger side. The other three were soaked! It's going back to the dealer, but any thoughts? Common problem? All my trim seems to be in place.

Thank you, Dave

 

Give this a look: Wet floors

 

It seems a little unusual for a 2018 to have the wet floor problem.

 

I've read that, but hoped they'd have this worked out by 2018. I like the Fit overall (especially driving a six speed), but I've been back to the dealer for problems twice already. I didn't expect this from a new Honda. Glad to hear it's not a common problem, hope the dealer can fix it.

 

I had the leaky trunk in the 08 I owned. I have a 2017 now. I haven't noticed any problems. Maybe a seal or something is clogged and that's what is causing the problem. Just a guess though.

 

What I've seen with leaks in the GK are sunroof drains and the plastic barrier behind the door panels not sealed properly. Since you've got a sport, then no sunroof so I'd guess it's the plastic barrier behind the door panels.

 

I've done a bunch of reading thanks to this site and I see what the problem is... seems like a design flaw that should have been fixed years ago. Maybe they stuck rubber floor mats in hoping I wouldn't notice? Anyway, I'm hoping the dealer will fix it for me. I have the tools to take the doors apart, but a 2018 with just a bit over 200 miles should not have water on the floor.

 

Ended up cancelling my appt. with the dealer. We had a heavy rain yesterday for a good 6 hours and my floors are totally dry! Over the weekend we had a light rain for a day and it left me with two puppy pads (that's how I soak up the water) full of water. The only difference is the light rain happened while the temps were close to freezing and the heavy rain we were in the mid 50's. Maybe ice played a factor last time? I'll continue to observe.

 

Hey Dave
The ol GD3 has a problem under that black strip on the roof. Towards the back the seam sealer cracks and the water comes down the side and right into the foot wells!
GLWR

 

Assuming that the leaks are in the front, then another path for water to enter might be the wire bundle cover in the door, either connected to the car's frame (I would guess probably likely) or connected to the door itself.

 

 

I didn't have wet floors this morning, but I noticed the driver front window was really foggy and the driver rear window had some ice on it. The passenger side was completely fine!

The drive home yesterday had a lot of sleet and snow, but then I parked in my garage. This morning's drive was dry, but it was about 10*F outside.

When I upgraded my door speakers, I bought these and installed them behind the speakers. I figured they were cheap insurance: https://www.crutchfield.com/p_237XT6...mnews=15040450

 

i had this same issue on a 08 fit now on a 15 fit

 

 

Make sure the drain holes in the bottom of the doors are clear,,
Road slime and grim can run in there and clog them.. Its the biggest reason
many cars rust at the bottoms of the doors.

You can clean them easy with a pipe cleaner from the bottom..

 

I have a 2015 Fit with 60,000 miles on it. Has always been an excellent car with no issues, but I have been dealing with these leak for about 4 months now. I noticed it one day after a heavy rain. Before you skip my post and refer me to the vapor barrier thread, IT IS NOT THAT.

Originally both rear floor boards and underneath both front seats (but not front floor) were sopping wet. I couldn't find an obvious leak at first, so I took it to a local shop. They water tested and made up some lie about my rear window seal being bad and replaced it. Still leaking. They basically told me to screw off, so I threw $400 out the window there. Decided to investigate myself with the help of some friends, but couldn't find a real obvious leak. After finding the vapor barrier thread, I found water getting in underneath the door trim, so I suspected the vapor barriers. After extensive water testing, I found no other leaks. I had a Honda dealer replace the vapor barriers (paid $400 for a lazy tax). The dealer denied that the vapor barriers could be causing this leak, but I showed them the barriers had come detached from the door, and where water was getting in. They agreed to fix, but said they didn't think it would fix problem. Still leaking one week later. Take it back to a Honda dealer for a water test (should have done this in the first place but didn't want to shell out $550 for a diagnostics), and they found that my front driver door has a broken water run channel, and the door drain is plugged. They fixed everything (unfortunately it required new parts, disassembling door, new vapor barrier on front, putting everything back together) and ran me about $600.

While my car was in their custody, they backed the car into another car in the shop bay going about 5-10 mph. At this point I can't believe my luck. The damage wasn't terrible, but required a bumper replacement. No structural damage. They tell me they will obviously fix the car, pay for my rental, Honda OEM parts etc. I get the car back a week later after the body shop fixed everything. The bumper repair was done well, they water tested it twice, and everything checks out. I'm thinking this ridiculous saga is done at this point.

Fast forward a week and my rear passenger carpet is wet AND I now have a ton of water in my spare tire area, which wasn't there before. I take the car back in. They cover my rental. They tell me a body seam cracked from the accident. They fix it. I get the car back.

A week later I still have water in my trunk. Take the car back in. They cover the rental. "We forgot to reroute your sunroof drain. Easy fix."

This was two weeks ago. I have the car back. Everything seems fine, except today after a heavy rain my rear passenger carpet is slightly wet.

The trunk leak is fixed. The driver side is bone dry. But that passenger rear side will not stop leaking. I have no idea what it is. Two different dealerships can't find the leak in four different visits. An independent repair place can't find it. I can't find it. I've stripped the carpets and gone through car washes sitting in the back seat and seen no water getting in. The drain plugs on the doors are clear and running fine. My sunroof drains are fine (I'm assuming since they just rechecked and routed them last time). I had the vapor barrier replaced on that rear door already.

HELP ME FIND THE LEAK.

This car is almost paid off and I'd like to enjoy no car payments for awhile. I'm really close to just trading the damn thing in for a Mazda 3 or CX-5 though. This has been so frustrating. It's been months and about $1500. I've driven Hondas all my life and never had a problem until now.

 

Might want to double check the sunroof drain. There are 4 drains if you can believe it! You can see some details on AJ's thread: Action Jackson's tinkering

Sorry about the troubles, sounds like a lot of it was caused by an inept dealership.