Wet passenger floor

99' Grand Prix Gt Coupe

I just started to notice that my floor is really wet on the passenger side. I have just started to use the heat more since it has been so cold in the morning. In the summer I had some work done on my evaporator core because it was clogged and was leaking water on my passenger floor. There is no more problem when I use the air conditioner. Since I started using the heat I noticed it wet. I took up the mat and carpet and found no liquid to be comming from the top. Its on the bottom jsut infront of the seat. Checked the fan and all the opther stuff under the glove box and there is no water comming from there. Its jsut water so its not a heater core cause its not slippery from anti-freeze. Does any one have any ideas on what this might be it would be greatly appreciated. Thank you!

Usually it means your A/C drain is plugged. You will have to unplug it.

You can install a cabin filter from a Buick Regal to help prevent this problem in the future.

It could be the condensor but it could also be the seal underneath the cowl below the windshield. My old 97 GP, and many others, had this problem. There is a rubber seal that channels the water away. If this is loose or fallen off then the water will go straight into the blower and leak onto the floor. Check that because you may need to reseal it.-

:confused: I have a 2000 Grand Prix GTP and the same thing just happened passenger side has an inch of standing water after the heavy rains we just had. The dealership says it's seals that are torn (like, HOW would that happen?) and he has to pull out the windshield cowelling (whatever that is) and it'll cost like $700. I'm in crisis! The hub assemblies ($900) in the front also need to be replaced, and neither thing can wait. Isn't there something I can do myself about the leak?

Looks like a bunch of people have had similar problems. Makes me think that maybe Pontiac should repair it on their own dime. Maybe this kind of thing just happens, though.

yes - i just did a job on a 97 with this problem - it seems you guys have the problem that she did - i took the cowl off - an the underdash on pass. side - i ran water from outside an watch it - it ran in where the box is on the firewall - there is a blower motor toward the front of this, but if u take the black blower box on the fire wall off there will be a neopreme kinda gasket - i went to the local GM dealer got one for 12 green backs - cleaned up the surface area with alchohol swab. installed new one ran some more water an it stopped.... the old one was acually mashed on the bottom left side --- your gonna have to replace that seal or do a damn good silicone job on it hehehe - goodluck

I hear crazy loud sloshing when i accelerate in my car, mechanics have told me it is most likely a problem with my heater core and or coolant system. There is no water leaking into my car though, i'm still
confused.

if they are a mechanic an have checked it out dude they should not be giving you a - answer like - It is most likely - they should be like - ya thats your..... like check it out - would you rather have your car most likely working an safe to drive ? or workin an safe to drive? see where i am coming from....

By the way where is that sloshing sound like its coming from so i can see if i can give ya any help on this ...

It's infront of me, it sounds like behind the dash, a rather loud noise, like a gallon of water going "SLOSSHH". I can easily hear it over music playing if i accelerate on a turn at over 3000rpm.

k i am really tired man - i will help ya on this tomorrow sorry- i gotta get up in 4 hours ... but i can say one thing if its coming from the driver side it isnt the heater core because that is on the pass. side lol - see what did i tell ya good mechanics eh... talk to u tomorrow man ....

oh i forgot to mention that i took the entire floor out of that 97 the the leak cause the carpet was rank an moldy - so it was also easier to see where it was coming from - so i would pull up the carpet on the pass. when do it for those of you that have the leak on that side - oh an when you want to dry it out - put a dehumidifier in an let it run over night you will be surprised at how well it dries it out even over an inch of water :) good luck