Leak into cabin

I own a 2005 Toyota Pries that I have been extremely happy with. I now have experienced my first ?problem?.
I have a wet carpet on the passenger side floor. I noticed it first as a slight wetting of the flat area closest to the firewall after we had some rain. It has gotten much worse now being a visible puddle of water after the last rain storm we had. The water is leaking down from the plastic ?overhead? area above the ?transmission? hump between the two seats and under the dash. I can theorize this is rain water from the windshield area that has failed to drain out because of a blocked drain passageway but I don?t have any idea how to find if this is so. I have cleaned all debris from the vents at the base of the windshield with no improvement. Any advice would be great!
Gary

Hi Gary. Sorry about your leak. It probably is coming in from the outside, but there's a small possibility it's coming from the air conditioner. Unless it leaked from the start, it probably isn't a faulty seal around the windshield (unless you have had your windshield replaced.)

Do you hear any "sloshing" behind the dash? If you do, the condenser box of the air conditioner may be blocked. The AC can run when it's humid (i.e., raining outside) to clear the glass of fog. The easiest way to get this fixed is go to a service station with a lift and have the mechanic blow air up the drain to dislodge any debris. Water runs out the drain, problem solved.

If it's not the AC, there are a couple of drains on either side of the car near the side that can get plugged, particularly if you park outside and stuff like pine needles can get down inside. Unfortunately, they are not too easy to get to to clean. You have to remove the wiper arms and the black plastic cowl at the base of the windshield. If you are really handy, you can do it yourself, otherwise, take it to a service station and have somebody else do it.

As a 2005, is it still under warranty? I'm pretty sure the dealer can figure out what's wrong and fix it. You want to get it fixed as soon as you can. A wet carpet can grow mold and then the carpet (or more) has to be replaced.

Bill Merchant

Thanks for the response Bill.

I reside in Buffalo, N.Y. and it has gotten colder here and although I have never turned on the air conditioner I have used the air/auto setting and the air conditioner may have been coming on without my knowledge.
As it has gotten cold in the morning I now use the defroster setting and then the defrost/feet setting to clear the windshield which I am not positive but I believe negates the air conditioner. At any rate it has rained at least 12 hours straight and the carpet is bone dry making your air conditioner theory the likely answer. I will have it checked out the next time I take the car in. I must be honest with you; I don?t normally take the car to the dealer as the maintenance is pricey to me.
I have an experience I will share with you in payment. Last winter when driving up slippery (icy) hills the ESC, electronic stability control would kick in and because both wheels would spin in the slippery conditions I would lose forward drive to the point that I might end up crawling up a 55 mile an hour highway at night in a snow storm; a very dangerous situation indeed. I was able to take a run at the hills to prevent most deceleration except the longest hills but that had its own set of dangers. I have had a similar experience in deep snow going up a driveway to a house on a hill but not to this extent. I see that some manufactures have an ESC defeat switch but I digress. This summer I replaced the original tires as they had over 30,000 miles on them. So about two weeks ago we had a major freak snow storm, I live at the bottom of a hill and with the road very slippery I would have expected the ESC to give me problems but in fact it did not cut in at all. I believe my problems with the ESC last winter was from worn tires causing poor traction and I hope and expect that I will not have the same problem this winter.
Gary

Hi Gary. The Defrost setting on the climate control will turn on the AC Compressor as well as the heat. Warm air can hold more water vapor than cold air; when the cabin air is cooled passing over the AC condensor, water vapor is condensed to liquid water, which should drain out onto the ground under your car. The dried air is then sent over the heater coils to warm it to a comfortable temperature and blown out into the cabin. This is the process used to take the interior fog off the windows.

When the condensor box can't drain onto the ground, it has to drain somewhere, so maybe it was dripping inside on the carpet, where it evaporated into the air and was removed again. Clearing the condensor box drain is fairly easy, like I said before, and just about any shop with a lift so you can get under your car can fix it. I thought your Prius might still be under warranty, which is why I suggested the dealer.

As for the tires, the Goodyear Integrity tires which come on the Prius are low rolling resistance, but that's about their only good feature. For your winter snow/ice driving, you might consider getting a winter tire. Nokian Snows (Hakkapeliitta RSi - pure winter tire or their WR - also good dry) are highly praised on PriusChat.com.

Bill Merchant

Gary, I've had the exact same problem on my 2003 model. It seems to happen only when it rains. The first time I noticed it- it happened on the passenger side, front seat. Last week it happened on the driver side....I wonder just how common this problem is? Good luck, Yvonne

Yvonne:

I have found Toyota vehicles to be the most reliable vehicles I have ever owned and Consumer Report agrees with me. I am amazed that a complicated mechanical product such as an automobile can be this reliable. As I wrote the last time it rained for twelve hours and the rugs were bone dry. I am making an effort to keep the air conditioner off by using the manual climate control settings to set for defrost and defrost plus heat and disabling the air conditioner. It does not get that hot in Buffalo N.Y any time of the year and I like the better gas mileage. To this point I have not had the problem again. Good luck to you
Gary

Hi Gary......I have a 2006 Prius with the same problem of leaking when it rains. I read some of the replies to your post and I am not sure it is from th A/C condensation. I never use my A/C. The problem seemed to develop after I owned the car 15 mo. or so. Have you got any new answers?

OK, this is IMPORTANT... When you read this about water inside you car make sure that you use a WET/DRY shop Vacuum or you could get shocked or worse! I went to a local repair shop and asked why the inside of my 2005 Prius was always wet and mold was actually growing inside on the carpet. The mechanic said that my air conditioner condenser overflow valve was plugged and the water that the air conditioner creates has no place to go so it overflows into the cabin of your car. He suggested that I go home and take my WET/DRY shop vacuum, pull the plug out of the floor board and suck out what ever was in there. I did what he said and all this water and gunk came out, problem solved! Now remember to use ONLY a WET/DRY vacuum when doing this. The drain tube/hose on my car is located inside the cabin on the passenger side of the car up at the top of the floor board (about where a large mans left toe would be if riding in the passenger seat). First you must reach up and pull the carpet back to expose the drain tube. It goes through a round grommet or o' ring and outside underneath the car. Just pull the grommet out (you may need a small flat screw driver). Once the grommet is popped out and the tube end is exposed take your WET/DRY Vacuum and put the end of the drain tube in it, turn on the vacuum and watch what happens. You should at least see water gushing out. You may need to use your hand to create a better vacuum when you put the drain plug into the vacuum hose but it worked right away with mine. Its been quite a while and I drive with the air on every day and the problem has not returned and the fix was FREE!