Wet on the passenger's side?

Have you check the A/C drain tube? If you live where pine needles or such can get into small areas they can plug the drains and then it will collect water rather then drain.

This video will help us fix it

https://youtu.be/q9_MZiS2_NE

Please run down this guide and report back.

I tried blowing out the drain tube and was able to hear airflow inside the car. I also took off the plastic cover below windshield/wipers to see if water was sitting in the frame but there was none.

The radiator is full correct? Just checking start back with the simple and go from there you know.

Yes the I checked the radiator and that was full

You might be hearing the water move through the heater core, this happens when air gets trapped inside the core, try to run the engine hot and then jack the rear of the car up this will help purge the air out. This guide will help you

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

Please run down this guide and report back.

I have a 2001 Pontiac Grand Prix GTP. The engine is 3.8L V6 FI OHV. I just noticed the floor is very wet on the front passenger side of the vehicle under the mat. I looked under the car to inspect for rust or holes and did not find any. I heard that these cars sometimes have an issue with a water track where water runs off from the wipers. If clogged or rusted, this can cause water to come into the car. Can it be this or is there something else it could be?

Could be the heater core leaking or the AC drainage tube is clogged-up and backing it up-could be leaking thru the windshield when it rains

You could have a clogged a/c drain hole on the firewall about the middle of it about half way down.That is the first thing i would check.

Hello. I have investigated several possible reasons of why the water is going on the floor in the passenger side. I have took the cowl off, made sure the rubber thing on the bottom of the windshield was on correctly..put new weatherstripping on the bottom side of the cowl. Took the glovebox out and watched the water drip onto the floor as water was being sprayed on the windshield. Watched the water pour into the car going down the road while it was raining. And I can not figure this out. It is going to ruin the floor in my car. I took the elbow off of the hose that come out of the firewall to the evaporator case to see if it was plugged. Blew air into the hose and you could hear it coming back into the car. Ran a wire into it and seems as if it's not plugged. Where is the evaporator case located? And does anyone have a solution to this?

If I understand, you can see water coming in when you spray water on the windshield. Is that correct?

Yes sir, the water drips onto the floor when you spray water on the windshield..the water drips on the floor when it is raining and you are driving down the road..the water will drip in when the car is just parked and it's raining. This is ridiculous..I can't seem to figure out where it's coming from..and it's driving me crazy..LOL. I don't know what to do about it. If it rains really hard..the floor will be soaked and the matt will float..have you heard of this before? Any help will be highly appreciated!! I read in another forum somewhere if the evaporator case gets clogged..not the hose in the firewall..the actual evaporator case that this causes a problem as well..but where is it located? And when you take the glovebox out..you can see it dripping on the wires and on the flap thing that opens up when you have your blower motor on..but you cannot see all the way up in there to see actually where it's dripping from..HELP..LOL..thank you :)

The AC isn't the problem. It sounds like the windshield needs removed and resealed. What to do is have it checked by a glass shop. They will know exactly where to look.

Let me know if you have other questions.

Joe

Passenger side floor wet. comes from base of seat, not dashboard. no smell, no warning lights. Remains the same in high heat but gets worse with rain. Does not puddle but always wet. Just took it to the mechanic, who claims air conditioning pipe is not clogged.

If it is not coming from the AC drain tube or heater core dismount the seat and investigate.

Hey Raz, just wanted to add to this one because I just had to deal with similar issue in shop. This is a some information from another Grand Prix owner that posted this on the web, I found to be helpful:

I also had the same problem and spent over two thousand dollars before i found out what the problem was. All Pontiac Grand Prix from 1999-2009 that leak water on passenger floor is from the following: The front cowl panel, [Where windshield wipers are] has a air box inside the panel, that when built has a two piece construction that is sandwiched together at factory, and over time, summer heat, Icy winters etc, dries out and allows water to get into air box and drip out below dash on passenger side. To fix: Remove wiper arms, remove cowl screen, and you will notice a box looking square on passenger side, clean out in and around box opening top. Must be clean and dry. Next use ether urethane windshield sealant, or silicone water proof sealer. reseal all the way around box , [Where metal body meets air box.] Make sure to re seal all the way around air box and let dry overnight. You can buy ether sealants at your local automotive parts store.

that would make sense, but it is not coming from the dash. it is coming from the seat area. the parts near the dash are the very last thing to get wet.

You might not think it is coming from the behind the dash, but try this, pull the carpet up and back starting up towards the dash and stick your hand under it. I think that you will find that the underneath is saturated with water, the carpet might not seem wet but there is about two inches of foam under the carpet that absorbs the water and it runs back and pools up in the passenger floor area.

Where might the water be coming from on drivers floor?

Could be a heater core leaking (coolant) or if using AC, it may be drain is clogged.

Definitly not coolant. Only happens when it is really pouring rain. Where and how do I check drain hose (?) on drivers side? Thanks.

If it only happens when raining, then it is faulty sealing around cowl or possibly windshield.

Is there a deflector, like the one I got for the passenger side, available for the drivers side, that you know of?

Check with local autoparts stores. There are many aftermarket shields available.

I noticed today that on the passenger side floor it is completely soaked. Seems the water is coming from when the air conditioning is on...

Wondering if this is some sort of repairable issue or something drain wise has gotten plugged?

I have no idea where to look, etc

Yes, it sounds like the drain is plugged. You have to locate the outlet where it drains through the firewall from the engine side and clean it out with a coat hanger or compressed air.

I have had ny car for about 2 yrs now and this problem will not go away. Everytime it rains hard, the front passenger and the rear passenger floors hold water. Sometimes about 2 inches. I have tried to ignore it but when it drys it smellls sometimes. Is this a major problem or do I just need to get the rain and vent ducts cleaned out. The car has been in no accidents and the windows have not been replaced. How much does a rain duct cleaning cost? Can I do it myself?

Does it have a sunroof?

got a 2002 pontiac grand prix it does the same thing and no sun roof

If it has a sunroof, it's probably a restricted sunroof drain. If no sunroof, It's probably coming in through a front door water deflector behind the door panel. It could also come in through the cowl area near the fresh air intake opening.

I knwo it's been awhile since you asked this question. But I had the same problem with my 04 Grand Prix. There is a Seal at the bottom of the windshield under the hood that has fallen off and letting the water in. Just get some silcone and put it back on. Havent had a leak since. It's been 1 1/2 years now.

2 questions -

I have a leak near my sunroof...any ideas?

Also, I washed my car yesterday (all windows up, doors closed, etc.) and I had water coming in on the passenger front near the firewall.

You will most likely have to remove and reglue the weatherstripping. 3M makes an excellent product.

The water from front is also weatherstripping, unless it smells like coolant in which case it would be heater core.

I'm getting a wet passenger side floor (front and back) every time it rains. I believe the water is coming in from somewher on the firewall or cowl. The windshield or windows are not leaking. Any suggestions?

Do u have sun roof
if so I would check and clean drains in it
open sunroof and check corners
u can use compressed air and blow throw the drain holes

I am having the exact same problem on my 2000 GTP.

Have you found where it is coming from?

if have a sun roof do as advice up
problem was solved
95% its clogged


check if u r ac drain clogged too

I had this problem on my 2000 GTP without sunroof. Turned out the plastic cowl over the blower motor inlet was letting water into the blower motor opening. This was soaking my carpet, blower motor and blower motor control. It cost me about $300 in parts to replace the blower motor and the blower controller (automatic climate control). Now it is leaking again, so I have to fix the cheap plastic cowl again where it is "supposed" to seal against the windshield and keep water out of the gaping hole for the blower motor.

I had found a write-up of a fix for this, bu I can't find it right now.

2005 Pontiac Grand Prix

I have a 2005 Pontiac Grand Prix that is leaking water on the passenger side floor boards. It is water, not radiator. It puddles after it rains, no visible sign of water any where but the floor. We put a hose on top the car, pulled the carpet back and saw where it was coming in at the floor but don't know how it is getting there. I called a windshield place and they thought it might be a clogged drain hole. Where is the drain hole located so I can check?

Here's a link...

clubgp.com/newforum/tm.asp?m=2398123&p=2&tmode=1&smode=1

Once I figured out the best terms to search for I found it. There are literally hundreds, maybe thousands, of topics on the net about this problem specifically with 97-03 Grand Prix's. This should help.

They may have been referring to the A/C Evaporator Core drain pipe, but this sounds like a weather stripping issue.

A plugged A/C Evaporator Core drain can backup and get water into cabin, but only if AC is on.

It is most likely a windshield weather stripping issue.

You may have to have windshield removed and re-stripped.