Leak in Passenger Floorboard?

[la79]

Hello,

Just wanted to know if anyone has experienced any issue during rainstorms that your front passenger floorboard gets wet? But only your passenger floorboard? I've noticed this only happens during rainstorms. Now that it's been getting cool I haven't used my AC at all.

I noticed that it gets wet on the AC blower motor assembly along with the radiator core which are both below the glove box and also behind them on the floor.

I know it's not from the Heater core or radiator fluid as this only has been happening during heavy downpours and just water.

I've removed the cowl and have literally done a splash test with a hose but can't figure out for the life of me where it's coming from.

I don't have a sunroof, but would anyone know if there are any drain lines that run through there? Also, it's not my washer fluid line either as I know that runs through the side footwell and I don't see it leaking at all when I use it.

I've done some searching all through the the forums and on Google but can't get any answer on what the problem might be.

I was beginning to wonder if it's the bottom of the windsheld if water is leaking through there and just running inside the car and down.

I found this post just to get an idea of what exactly is behind the glovebox:
https://www.toyota-4runner.org/3rd-gen-t4rs/124887-heater-core-removal.html

Anyhelp is appreciated.

 

[phattyduck]

If you removed the cowl panel (base of windshield), you should be able to look over to the passenger side to see the air intake for the AC system. It should be a little 'chimney' that should keep water from flowing down into the AC system. On each side of the lower cowl panel, there will be drains to let water out behind the fender.

You likely either have plugged drains or a rusted panel below the upper cowl panel...

-Charlie

 

[la79]

Thanks for the advice. But when I remove the plastic trim cowl I see a metal frame and no where do I see drain tubes. Are you saying the metal frame can be removed? Attached some photos to show you what I’m talking about. This isn’t my car but it’s the same.

Are these AC drain tubes used during rain storms to clear out water that lands in the cowl?

 

[phattyduck]

The fresh air intake for the AC is below where the 'fourth' intake would be in the cowl panel. It is covered above to keep rain from falling straight in. You have to peek in through the other holes to see it. The water drains from that space on each side, behind the upper corners of the outer fender panels.

Visible here, just in front of the upper door hinge:

AC drain for the evaporator is lower on the body, on the firewall where the exhaust goes down. It is just a stainless steel elbow that comes out and goes nowhere.

-Charlie

 

[la79]

I see what you mean now. Thanks for the explanation.

How would you go about cleaning it out if it’s covered by the metal frame on the passenger side? Only thing I can imagine is removing the passenger fender flare? Or can it be accessed through the wheel well? Doesn’t seem like it can on the drivers side.

 

[rkntoy]

Do you have a sunroof?

 

[sportscarfan]

Check where your headliner meets the windshield inside after it rains. Is it wet?
My bet is the leak originates from anywhere across the top of the windshield. Here's how it happens...
A previous owner had the windshield replaced. The shop / installer uses a common tool to cut the old windshield out. In the process, scratches the paint on the flange the windshield is glued to. Zero F's given, they lay their bead of sealant and slam the new windshield in.
The rubber "seal" that goes around the windshield is mostly decorative and does not stop water from intruding past it. The water sits behind that seal and on the scratched metal of windshield flange and slowly rusts until it's so bad it starts to leak through.
It could also be a void in the sealant and water is coming in somewhere at the A piller.

 

[phattyduck]

I see what you mean now. Thanks for the explanation.

How would you go about cleaning it out if it’s covered by the metal frame on the passenger side? Only thing I can imagine is removing the passenger fender flare? Or can it be accessed through the wheel well? Doesn’t seem like it can on the drivers side.

Look/reach in through the other access holes. Not much to access from the side behind the fender - both sides look like what is pictured above.

Also, as the other posters mentioned, winshield frame rust and sunroof issues are also high on the list of possible causes. I went this direction because you mentioned that the water seemed to be coming down the firewall above the AC system.

-Charlie

 

[la79]

Do you have a sunroof?

Nope, no Sunroof.

Check where your headliner meets the windshield inside after it rains. Is it wet?
My bet is the leak originates from anywhere across the top of the windshield. Here's how it happens...
A previous owner had the windshield replaced. The shop / installer uses a common tool to cut the old windshield out. In the process, scratches the paint on the flange the windshield is glued to. Zero F's given, they lay their bead of sealant and slam the new windshield in.
The rubber "seal" that goes around the windshield is mostly decorative and does not stop water from intruding past it. The water sits behind that seal and on the scratched metal of windshield flange and slowly rusts until it's so bad it starts to leak through.
It could also be a void in the sealant and water is coming in somewhere at the A piller.

Thanks for this. My headliner was not wet when this happened. Nor was the top of my floor mats. Just underneath them. Also, couldn't see anything on the bottom of the windshield at all. I've had the windshield for close to 5-6 years now and never had any issues with leaks so I would assume a leak would have happened when it was originally replaced.

Look/reach in through the other access holes. Not much to access from the side behind the fender - both sides look like what is pictured above.

I'll try to remove my cowl again and see if I can reach in there. Appreciate the tips. Hopefully I will find something soon and report back.

 

[Sparky 97Runner]

Water will track down the antenna cable to the location you describe if there is not a proper drip loop inside the fender before it enters the cab. Try spraying water around your antenna as a test.

 

[la79]

So over the weekend I went ahead and took apart my cowl, the inner fender wheel well and removed took apart my passenger foot well. I also dumped two bucket full of water in the windshield and over the cowl area and found no leak. Lastly I sprayed my ac evaporator drain with compressed air and ran my ac a bit but no water either.

I’m actually at a lost and short of just sitting in my car when it rains next time just to see where’s water gets in.

Does anyone know the signs of a bad heater core? I do get slightly fogged windows but nothing drastic could be just a cold window and hot air from the heater.

Totally confused and will continue to keep checking.

 

[Bad Luck]

So over the weekend I went ahead and took apart my cowl, the inner fender wheel well and removed took apart my passenger foot well. I also dumped two bucket full of water in the windshield and over the cowl area and found no leak. Lastly I sprayed my ac evaporator drain with compressed air and ran my ac a bit but no water either.

I’m actually at a lost and short of just sitting in my car when it rains next time just to see where’s water gets in.

Does anyone know the signs of a bad heater core? I do get slightly fogged windows but nothing drastic could be just a cold window and hot air from the heater.

Totally confused and will continue to keep checking.

A bad heater core will leak coolant into the hvac box and then out of the condenser drain or onto the passenger floorboard. Vehicle will likely start to overheat and make gurgling noises from air pockets in cooling system. I recommend setting up a sprinkler or a wide area fan sprayer on your vehicle and then hang out in there for an hour or so to see if anything leaks.

 

[phattyduck]

I’m actually at a lost and short of just sitting in my car when it rains next time just to see where’s water gets in.

Does it get wet when parked, driving or both?

Do you still have your factory windshield or has it been replaced? Have you checked around the windshield for any signs of rust, damage, leaks, etc?

Are you 100% sure water is coming in near/above the HVAC system under the dash?

-Charlie

 

[CB3G_GM]

I had the same problem which turned out to be multiple things (one due to a collision which I imagine you have not had.) Visually inspect the grommets for the AC hardline (evaporator) and see if they look loose (wiggle them a little as well). Try pouring water over this area and recheck for leaks.

I took my dash out to verify this was one of the points of ingress. For some reason the way water is diverted in this area during a heavy downpour causes a fair bit to run down the firewall onto these grommets. I wanted to avoid pulling the evaporator to replace the grommets so I got some flowable rubberized silicon, cleaned them up and applied liberally. 3 years no leaks.

 

[phattyduck]

a heavy downpour causes a fair bit to run down the firewall onto these grommets.

Good thought. The driver's side wiring boot has water POUR over it in heavy rain / car washes. There could be something like that on the passenger side for sure.

-Charlie

 

[Xjazzwreck11]

I am having this exact same issue on the passenger side floor. I did recently repair my antenna so there is a chance I did not put it back in with the "loop."

Does anyone have a photo showing how this loop is supposed to look by any chance?

 

[Sparky 97Runner]

I am having this exact same issue on the passenger side floor. I did recently repair my antenna so there is a chance I did not put it back in with the "loop."

Does anyone have a photo showing how this loop is supposed to look by any chance?

Sorry, I do not have a picture. Just make sure that there is enough slack in the cable inside the fender and that it hangs down below the point of entry to the cab. This allows the water tracking down the cable to fall off before it enters the cab. It doesn't have to be pretty. It's a fairly common problem when people change out their antenna on other vehicles too. This is all that is meant by "drip loop".

 

[Xjazzwreck11]

Got it, I guess I will be pulling the fender apart yet again! :bounce:

 

[la79]

Just following up on this issue. I finally found out that it is indeed a windshield leak. It's now happening on the drivers side.

I will be looking to remove the windshield and resealing it. Along with replacing the windshield dam and trim.

Appreciate all the help and advice in trying to find out the problem!