2005 Avalon water leak under driver's seat - Toyota Tundra Forums : Tundra Solutions Forum

jryan02 · #1 (**permalink**) 07-05-2007, 12:43 PM

My 2005 Avalon XL has wet carpet under the driver's seat in the vicinity of the heat/ac vent. Some signs of water passage (rust) on heat/ac vent. Any TSB's or suggestions as to cause. Bought car new in August 05, maintained meticulously with 15k. No operation through standing water.

Found TSB BO005-07 (revised) and TSB BO015-03 (revised). Latter TSB enumerates numerous causes for cabin leaks. Dealer (Millennium Toyota) located leak source as "HVAC evaporator drain hose plugged with debris".

mustang67408 · #2 (**permalink**) 07-05-2007, 06:45 PM

The A/C evaporator on your vehicle is in the middle of the dash. Attached to the bottom of the EVAP box is a condensation drain hose, that allows condensation to drain out of the vehilce. If this drain hose was improperly installed or plugged from road debris or rodents or???? whatever, The water will fill the evap box and start to drain out the floor vents or wherever it can escape.
You need to check this hose, it might just be disconnected and draining water onto the floor.

Go to the passenger side of the vehicle, pull the carper out from the floor near the center of the dash. The hose should be attached to the lower side of the evap case. It is very visable, you should be able to see if it is attached properly or pinched or plugged. It runs back towards the passenger seat then goes thru the floorboard.

If that is ok, then there are some holes in the bottom side of the vehicle that are used to tie the vehicle to the car carrier when they are delivered to the dealershiip. When they PDI a new car they are supposed to insert the oval plugs that come in the glove box into thses holes, if they dont and you go thru relativley deep water, it will get into the floor of the vehicle.
You can crawl under and check, they are about 2" LONG OVAL HOLES that should have rubber plugs in them, somewhere under the driver/passenger feet and the driver/passenger rear seat. There are 4 in all.

Let us know what you find.

Mike Murrell · #3 (**permalink**) 07-06-2007, 04:28 PM

It would be interesting to know how an evaporator hose on a vehicle this new got plugged?

I do not know the design, but would have to wonder about how the hose is routed "outside" of the vehicle - down near the firewall where it drips.

Could it be the car has been driven down a lot of muddy roads and dirt debris have somehow plugged the hose near the end where water exits?

mustang67408 · #4 (**permalink**) 07-06-2007, 06:09 PM

Quote:

Originally Posted by Mike Murrell

It would be interesting to know how an evaporator hose on a vehicle this new got plugged?

I do not know the design, but would have to wonder about how the hose is routed "outside" of the vehicle - down near the firewall where it drips.

Could it be the car has been driven down a lot of muddy roads and dirt debris have somehow plugged the hose near the end where water exits?

You'd be surprised at what might happen to "NEW" vehicles.
I had a "NEW" Tacoma come right of the transport, it would barley run. Turned out to be a mouses nest plugging the filter box.

The hose connects to the bottom of the evaporator box, then makes a turn towards the rear of the vehicle, and follows the console where it exits the floorboard under the passenger seat area.
Pull your carpet back, you will see it. If it is missing/kinked or remove it and make sure it isnt plugged.

Mike Murrell · #5 (**permalink**) 07-07-2007, 12:54 AM

Quote:

Originally Posted by mustang67408

The hose connects to the bottom of the evaporator box, then makes a turn towards the rear of the vehicle, and follows the console where it exits the floorboard under the passenger seat area.

Well color me stupid! And shoot the bastards at Toyota for designing such a totally ludicrous drain path.....route the plumbing under the drivers seat......DUH???

Whatever happened to routing in parallel to the firewall???

I'm not raggin' on you '67 Mustang....thanks for the plumbing schematic.

I think I'm going back to American cars.

Heatwave · #6 (**permalink**) 07-24-2007, 03:11 PM

The Avalon is an American car.

Harsh · #7 (**permalink**) 09-12-2007, 11:41 PM

My wifes old Camry developed this all of the sudden. On inspection, the damn drin tube was gone!!! Had been fine for years. All I can figure is the oil change guys must have took it out, or someone stole it, which I can hardly believe that. I had another run in at the oil change shop later with my vehicle, and we stop going there.