Water leaking under dash on passenger side.

Whenever it rains, or sometimes just when washing my truck. I get a major leak under the dashboard on the passenger side. It seems like it is coming from the a/c, I have no idea where to begin with this problem. I was hoping someone on here might have any sort of advice, before I take it in to the dealership. Oh yeah, my truck is a 99' tahoe 2dr. 4x4.
Any info would be greatly appreciated.

Sounds like a heater core to me.

Whenever it rains, or sometimes just when washing my truck. I get a major leak under the dashboard on the passenger side. It seems like it is coming from the a/c, I have no idea where to begin with this problem. I was hoping someone on here might have any sort of advice, before I take it in to the dealership. Oh yeah, my truck is a 99' tahoe 2dr. 4x4.
Any info would be greatly appreciated.


By any chance have yu ever had a new winshield installed ?? The reason I ask is I had the same problem after a new windshield. It turned out to be a screw missing in the plastic cowling along the winshield and the hole is right over the fresh air intake. Everytime it rained there was a puddle on the floor mat. Just a thought, But it may be worth checking out. On the passenger side there is one screw in a plastic cover remove the screw and lift the small section out, Under that is another screw that is right over the fresh air duct see if it is missing or loose.

Thanks for the suggestion. I bought my truck used and it has always leaked whenever there is a lot of water. I'll check for that screw you mentioned. Although one time there was a fire hydrant that someone hit on my street, and I decided to drive under the spray shooting 30ft. in the air (free carwash). Immediatley the water was literally pouring in on my passanger side. I ended up with about five gallons of water in the cabin after about ten seconds max. This was how I found out about the leak. I don't think that much water could be the result of a missing screw, but I'm willing to give it a shot. I hope it is the screw problem, because a heater core sounds like an expensive repair. Thanks

The4 seal on the windshield is leaking. Happened to mine a few times already...always after having the windshield replaced...not enough sealer

i have the same problem on my 2 door 97. been trying to find out where the water has been leaking in from for a couple of weeks now.

Also look and the vent box under the hood which is located under the coolant reservoir, mine was getting water in at that point.

i found this forum

http://www.automotivehelper.com/topic162432.htm

i took it to a auto glass shop and they told me wasn't the windshield. seems like the water is coming from above the heater. :banghead:

Thanks for all your suggestions, as soon as I have some free time I'll try to solve the problem.

i found this forum

http://www.automotivehelper.com/topic162432.htm

i took it to a auto glass shop and they told me wasn't the windshield. seems like the water is coming from above the heater. :banghead:


mine does tha same thing, 99 tahoe, it's where all ur ac/heat thing are, in there with tha heater core and stuff, mine only drips sometimes, i have some homyboys with tha same problems, 99 esclade, 97 gmc, 94 suburban, he says his sub blows a fine mist and will wet ur legs if u sit there long enough,lol funny huh, but crazy

By any chance have yu ever had a new winshield installed ?? The reason I ask is I had the same problem after a new windshield. It turned out to be a screw missing in the plastic cowling along the winshield and the hole is right over the fresh air intake. Everytime it rained there was a puddle on the floor mat. Just a thought, But it may be worth checking out. On the passenger side there is one screw in a plastic cover remove the screw and lift the small section out, Under that is another screw that is right over the fresh air duct see if it is missing or loose.


I had the windshield replaced with same issue, where exactly are these screws you are talking about?

I had the windshield replaced with same issue, where exactly are these screws you are talking about?
On the passenger side cowling at the bottom of the winshield. They have to remove winshield wiper arms and this when they replace the winshield. On the passenger side near the antenna you will see a single screw, Remove that screw and then lft the small section of cowling out. Under that small section is another screw for the center section. This is the one that leaked on mine and it is located right over the fresh air intake for the heater. Every time it rained I would have water all over my floor mat until I fixed it.

Same problem...my solution was the missing screw on the outside of the windshield trim (bottom). Water found its way down through the air intake via the hole where the screw should have been. Additionally, this plastic trim was cracked around the same screw hole, making it more of an issue. I solved the problem by replacing the screw and using silicone caulk on the crack and over the screw. I've been dry ever since.

My tahoe had the same problem but was the condensate drain hose. There was a 90degree elbow that was missing on mine. When I would run at highway speed the wind would blow the condensate back into the truck and not let it drain out.

Sure glad I am not the only one with this problem.Hope I will be able to fix this pain of a leak today.Thanks to everyone for the replys

Sure glad I am not the only one with this problem.Hope I will be able to fix this pain of a leak today.Thanks to everyone for the replysTook the cowl off and under foung the screw it looked ok but I put a drop of silcone on the threads and reset.NO LEAK after 5+" of rain in 24 hrs. THANKS

My 97 2dr. Tahoe leaks on the passenger side also. I back into my driveway which has a slight slope. I think the water is flowing down the roof into the top of the passenger door through the seal at the top of the door right by the windshield on mine. Is it possible that yours is leaking the same way? I get a lot of water on the floor in front of passenger seat and just behind it against the passenger side.

Sure glad I am not the only one with this problem.Hope I will be able to fix this pain of a leak today.Thanks to everyone for the replys
NO water after 12 " of rain the hole where the screw went in to filled with silcon reset the screw NO WATER.. Thanks for the post