I have an issue I was wondering if anyone else has experienced. Somehow the drivers side floorboard gets wet. I had to dry it out once last fall and currently am doing it again. It is only on the drivers side flat surface area. Its not wet on the firewall, the center hump or past the seat hump. (see pic).
I cant figure out at all how I'm getting water there. Its def. not coming in from the door jamb side or from under the dash. Its the strangest thing.
To top it off I have a floor mat, a piece of carpet and a rubber mat that my feet rest on, so it cant be penetrating down from my shoes. Its def. from the underside.


By the way, its an 02 Tacoma 4wd.

 

could be the windshield sealant leaking it will run down by the pedals and underneath the carpet it is really difficult to see, start spraying water on the truck with a hose and see if the floor gets wet, only do one area at a time so you can pinpoint it.

 

If you are running your A/C then the drain hose underneath the car is plugged. Push a wire up it to unclog it..... If that doesn't work you might need to replace your heater core

 

You might also be getting spray in around the steering shaft boot, it will sort of leach down to the lowest spot...
also if the carpet ever got wet once the underpad may be holding in the water... it feels dry to the touch but then it gets warm in the cab and the moisture seeps out... the only fix for this may be to remove the carpet entirely and take it to a paint shop and bake it in their oven for a few hours or something... I'm going to be replacing mine completely for this very reason...

 

I once had a similar problem whenever I hit puddles in or after the rain. Turns out that the hole in the firewall where the wiring for my dash slides through a rubber sleeve had started collecting moisture which ran down the wires and under the plastic panel in front of my driver side door. The water would flow under the plastic and down under the plastic coping along the door jam and then pool and spread into the flat part of the floor. I couldn't see any moisture in the carpet except for down on the flat part of the floor which really confused me. I checked that plastic sleeve and sure enough, where I had recently run a speaker cable and auxiliary fog light wiring was leaking. I got some silicone and gave a really good squeeze on the tube from the engine bay side and the driver's compartment floorboard entry side and that took care of the problem. No leaks a year after the repair.

 

Make sure you don't have any crap stuck in your sunroof drain pipes if you have a sunroof. If you blow some compressed air through them it should clean it all out.

 

Thanks Ed and DMONEY, you guys motivated me to spray it down and check those areas for penetrations. Sure enough I have my power wire for my amp going through the firewall behind the clutch slave cylinder. As i sprayed the windshield I watched the water flow down from my front cowl and run directly on the grommet where the wire is going through. As the pictures show, there is some sign of dirty water collecting behind the front wheel well below the wire and on the inside there's a little surface rust at the bottom of the grommet. It just boggles me that I didn't think of testing it out sooner. And just think, Ive had it like this for about 4 years now. Funny how water follows gravity. Hopefully this is def. the problem. There can't be anything else.

 

You'll want to get that power relocated fairly soon... you're lucky it did'nt wear through insulation and short out... if you want to stay in the same general area you might try following the "cowl wire" bundle in behind the front fender and through the grommet. You can get to it by removing the fender liner above the front wheel. There is also a bundle that comes through on the pax side in the same area.

 

I seem to be having the same problem. It's only on the driver's side and obviously coming from somewhere inside (not tracked in or coming from the top).

I have gone through many of your solutions here and this is my dilemma. I do have wires going through the grommet on the firewall and there couldbe room to get through there, but I have had it this way for years and have had no problems. Also, there are no visible signs from under the hood (rust, grime, etc).

I recently (last week) had my 4Runner serviced at the stealership at a cost of nearly $1100 to replace all of my fluids and repair my AC.

Because of this, I think it may have something to do with the AC service. I know the condensation drain tube isnt clogged because water streams out from under the car when the AC is pumping.

Does anyone know of anything specifically that the stealership could have messed up? I will continue to troubleshoot with the suggestions here, I just wanted to see what you all thought of this...

I want to know what to tell the service people at Toyota so it can be fixed on their dime. Help!

TIA!

 

I appear to be having the same problem on a new (to me) '98 4Runner. Wet floorboard on the driver's side. Discovered it last weekend when I pulled up my rubber floormat to shake it out. Whole flat area was pretty wet. Shop vac'd it up but now I've got that wonderful mildewy smell in the car. However, it seems to keep getting wet, mainly near the door.

I'm wondering if its the clogged sunroof drain because a couple weeks ago I accidentally left the sunroof flipped up over night. we got a light rain that night. I remember being surprised nothing go wet inside but I did wonder if there were drains up there that whisked the water away before it could get inside.

Is compressed air blasted through those drains the best way to clear them? I may also try to pull up the carpet and check the seal around the plug in the firewall. Can anyone tell me the easiest way to get the carpet pulled up?

 

Funny, had the same problem recently with my 01.
Can't figure it out.

On a serious note I was having the same problem on the passenger's side this summer.
But the water was just collecting on the floor mat

 

You should always run your stuff through a grommet. I go through the grommet and then seal around the wire with RTV sealant just to make it more weather tight.

 

Another common issue, typically for those that park their cars with with the rear higher than the front, is the incorrect installation of the vapor barrier on the tailgate. If they aren't in right, you get leaks. And if you leak at the rear, you'll puddle up front at the lowest point.

If it's not raining and you're getting water, it's the AC for sure though.

If you're not using the AC, and it's not raining, you sweat too much when you drive! =P

 

Tonight I starting tearing into this, pulling back the carpet and trying to figure out where the water was coming from. I'm certain its that same grommet. Based upon what all was wet underneath the carpet (flat part of the floor, incline behind the pedals, footrest to the left of the pedals) I traced it to that grommet. Dang if that thing isn't hard to get to and look at. But I could see where water had been coming through there, it was still wet.

So, I started by shop vac'ing as much of the water from the pad as I could, throwing away what was in really bad shape. Got everything as dry as I could. Then I pulled out the silicone and tried to hit that grommet 360 degrees around the hole, inside and out (engine side). Its tough to get to all sides of it, both inside and out but with silicone you can kind of just keep squirting and it will spread out. I've got a fan blowing on the whole thing right now, still trying to dry it up as much as I can. After that I'm going to get a pitcher of water and pour it from above the engine side of the grommet and see if I get anything water coming inside still. Fingers crossed.....

 

After the drive in to work this morning (still raining mind you) there's still some water coming in. I'm giving up and taking it into the dealer in the morning. I don't have the time or the energy to determine if its still the grommet or something else leaking.

 

May I ask how you fixed this problem?