Wet floor boards when it rains! How???

Anyone know how or why rain water is getting onto the passenger side floor boards and getting the carpet wet. It happens on both front passenger and rear passenger floor boards. It only happens in the area where your feet would be. It's only wet on the foot area on the front passenger and rear passenger, but it's dry in all the spaces between the front and rear floor boards

Front passenger:
-only wet on the flat surface area
-so sign of water where the black box to the AC drain thing is
-more wet in the center and kinda damp along the trim piece
-not wet under passenger seat or the elevated areas going toward the fire wall. Also dry on the elevated parts that lead up to the center console

Rear passenger (behind front passenger seat)
-more wet in the middle, where the mat sits
-wet where the mat kinda wraps around toward the side

Could it be comming from underneath? Perhaps water splashes up when driving and somehow seeps through

Or is rain water finding a way from a leak somewhere else like an "A" arm or door jams...?

Anyone experienced this or know of a cause?

I've read that its gotta be the black box thing but why would it be wet on the rear passenger floor board also, and dry in the between areas.

Here are a couple pics but you can't see the wet spots, so it's just pics of the areas that are wet.

 

I had that issue, with the evaporative canister drain being clogged with a mud wasp nest. It's on the pass. side firewall (years 03-04) slightly above the starter solenoid. Used a thick, long ziptie to jab continuously in and out of the drain hole. You'll know that's the issue if 2-3 cups of water starts dribling out when you've jabbed it a bit.

Other than that, the windsheid grommit could be leaking rain water in by the way of a bad seal or a loose grommit in the firewall maybe?

I'd start with the evap drain, if that doesn't work maybe remove the carpet, let dry, then run a hose first over the outside of the hood then the back side of the firewall to see where it leaks. There maybe things that you may not want to get wet in the engine bay? I'm sure someone else will chime in...

 

Mine does this on the driver side. I looked under the black plastic grommet that covers the seal for the windshield. In one are it looked like there was no sealant( truck came with an aftermarket windshield). I picked up a tube of that flow-able silicon and filled in the hole and the area around it. It has rained once since I did it and it did not get wet on the floorboard.

 

I had this problem on my last taco. In my case, rain would run down the driver's side window, into the interior of the door, out the drains on the bottom of the door, and then find it's way through a slightly damaged part of the door weather gasket. It would then amass in a puddle.

 

I seem to be having a similar issue as well. The floor is wet on the passenger and driver side in the exact same spot. It's wet on the flat surface area and does not seem to go higher up. It's only in the front area of the truck though (may be because I have an xtra cab).

This also happens whether I drive it or not. It rained last night and I haven't driven my truck in a few days and the floor board is wet today. My windshield was replaced a couple years ago, maybe a bad seal? I also have wires running through the grommets in the firewall. Mainmoe02, has your windshield been replaced? Do you have any wires running through the grommets in the firewall?

I've also noticed before there are plastic drain plugs in the area under the carpet where it is most wet. I'm thinking of applying silicone or something to it when I get the chance to and see if that does anything. I don't know why the floor would be so damp if plugs are in though which leads me to believe it is coming from somewhere higher up...I also checked the A/C drain and it is not clogged.

 

Does the floor get wet whenever it rains, or only if you drive when it rains?

 

I haven't checked enough yet to be sure. Im only going off of how it doesn't get wet when wash it and I spray plenty of water all over. Next time it rains I'll make sure to check before I drive off, Then check after ASWELL. As of right now it seems like it only happens when I drive and it's been raining or is raining. I didn't have this problem before I took my mudflaps off. Even after I took them off I didn't have this issue until a couple weeks ago and it's been raining more than usual here in Austin. I've checked under the floor boards and I don't see anything out of the ordinary. Everything seems sealed, no rust.

 

Toyota Technical Service Bulletin # BO 026-00. It's on this site somewhere, I only have a hard copy.

 

I checked last night after it had been raining for awhile and the the floor was only wet towards the center part. The carpet closer to the door trim, transmission hump and the firewall were all dry. I also checked the firewall grommets and they were dry. I think my leak is coming from the plastic drain plugs under the carpet. I guess the door is still a possibility but my the trim by the door wasn't wet.

Mainmoe02, I'm wondering of your leak is coming from the door somehow since only the flat part of the floor and the trim are both wet. The tsb mentions a leak at the door.

I found a link to a pdf of the tsb

 

I fixed mine. The hose that drips out through the fire wall is tricky because there are three parts to it and all of them have to be attached together. First is the plastic drain tube that has to be attached to the rubber hose at the firewall, then that rubber hose has to be attached to the metal nozzle (that is now in the engine compartment).

I found the rubber hose disconnected with the plastic tube that was were it was leaking all over the carpet.

Also make sure the a/c drain is not plugged as well.

 

Bringing this back up. My 1996 is getting wet in the very center of the driver side floorboard as described by these old post. Anybody had any further issues or any other discoveries of where to look?

 

While you sit inside your truck, have a buddy stand outside with a hose so that you can watch for the leak. Thats how I have found all of mine

 

Matt,

That what I did yesterday and could see it running down from the firewall above the rubber Grommet. Didn't want to spoil evening with family so held off looking anymore last night.

Got up this morning with intent to find and fix the issue but with stores closed i'm only got as far as finding where the water is entering the cab.

I tape the water hose to my windshield and while I was contorted down in the floor board I was able to see it entering right at the corner of the windshield and under the windshield wiper cover on the outside.

It enters high in that corner and then migrates down a plastic white shroud with wire bundles and also drips onto a round metal support (steering wheel) of some type. and then continues to the outside corner of the floor board and then down along the door threshold spreading out to the floor pan.

It looks like I'll have to remove the windshield wiper shroud to see whats allowing the water to enter the cab. Anybody ever removed the shroud? Whats involved? Wiper blades will have to come off it appears? Anything else? How exactly do the blade come off there spline shafts?

 

So after removing the wiper cowling and doing some more water tests I've determined the leak is from a void in the windshield sealant about 6" from the lower driver side corner of the windshield. It enters there and also at the corner.

I got some black adhesive/silicone sealant and sealed everything up and after about 7 hour cure time tested again and no water leak after about 7-10 minutes of running water.

And since I had the wipers, cowling, and most all of the panels pulled off the dash I decided to knock out some small Mods.

The wipers and cowling is sporting a new coat of Kylon Fusion Plastic black paint. The 4 194 and 2 74 LED bulbs are on order to finish the dash lighting Mod and once done I'll put all the panels back on

 

Just got done with this man, probably your weatherstripping. For 11 years that ain't too bad. Don't forget weatherstripping gasket, I used 3m

 

Dereck,

Yea I have a bad spot on the lower front door threshold that needs a repair or a new seal. But I think my water issue was from the windshield not having a good seal. I just got the truck about a month and a half back and we have not had any rain till just last week and it rained hard for 3 days.

How much was that seal and is it hard to change out?

 

I used OEM parts so the stripping was about $80, if my original ones lasted a little over a decade I'd rather pay that much now then go cheap for an autozone stripping.
I'd say it's a basic level 2 DIY project, just be sure to get some gasket too it'll help seal it

 

hmm I'm experiencing this on my driver side.. may have to try this

 

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