Water in drivers footwell

[dadsbmw]

So it's been raining a ton recently and I came to my e30 the other day to find that the carpet in the drivers side foot well is pretty well soaked.

I took out the seat today and attempted to get the carpet up to dry, but also tried to diagnose how exactly the water was getting in. I read up on a few threads which suggested it was either the heater core under the dash or some clogged drain etc causing the leak.

I warmed the car up and turned the heat on full blast and there was no dripping of any sort I could see. As well, took the hose and blasted all along the windshield/cowl area and not a single drop made it inside.

Any other thoughts where this could be coming from? The car is driven quite infrequently, so I doubt it could be a rotted out wheel well causing this.

[tomstin]

Under the HVAC box you should find three rubber drain tubes that drain through the transmission hump. They tend to crack and typically leak under the carpet. They are cheap, replacing them can be a test of patience, but worth the piece of mind.

Next, sun roof drains come down through the kick panel. I used string trimmer string to snake that all the way down into the rocker. Pour some water in from the top and make sure it drains to the ground.

Finally, the rockers have drain holes themselves that tend to clog from road debris. Make sure those are clear. The cowl and sunroof drain through the rockers.

Also, the door drains themselves need to be clear. And if the windshield lip has rusted under the gasket, that would make for a bad day. But start with the simplest and cheapest first.

[D.Martijn]

Water can also get in from under the fusebox is there is any rust on the seam between the inner wheel well and the firewall section.

[dsphil]

Remove the blower fan cover plate at the firewall and clean the trench. Water from the driver side vent drain thru the trench and down the elephant trunk on the passenger side. The trench often filled with dirt and water sip thru the 30 years old HVAC housing gasket.