Hey guys!
This is my first post and I really can't seem to figure this one out. I have a water leak under the dash in my 944. The water comes in under the passenger side dash and runs underneath the carpet kick panel in front of the passenger door. I looked up under the dash and can see water droplets on the inner material of the dash by the door seal, but also see some drops coming from further up, leading me to believe the seal isn't the issue. I also don't think it's my battery box because this leak is further back than the box and I resealed it with new seam sealer. I thought it might be the sunroof drain tube disconnecting from the connection through the firewall but I shined a light up at the connection as someone poured water down the drain and got no dripping, drain works fine and the battery box drain is clear as well. I am thoroughly stumped so any advice would be greatly appreciated!

 

Have your friend repeat the experiment, only this time, pour water in the battery box and see how much water flows in.

 

Dear MM..You didn't say what year your car was..If it's an early car, you could have a loose heater hose. They're way up under the dash on the early cars for the connections. Or it could be a bad hose. You also didn't say if it was fresh water or anitfreeze.. If it's antifreeze then it may be a heater hose leak. Later cars had the connections outside the firewall.. If it's fresh water, it's probably the battery tray. just sayin..

 

If it's a later car, be sure to check out the ECM..it's in the direct path of water leaks from the battery tray. A wet one will give you all sorts of problems later down the line. Early cars had the computer under the dash on the driver side so no problem there.

 

I bet you the sunroof drain tube has shrunk and then disonnected from the metal pipe that goes through the firewall. When this happens, water from the sunroof gutter runs down the tube and then just spills into the passenger footwell. The metal pipe is right below the windshield, so if this tube is disconnected it will look like the water comes from all the way up in the dash somewhere.

Take off the sunroof and pour some water into the front right drain hole. The water should run out next to the battery, then run down through the car and hit the floor behind the front right wheel. But if the tube is disconnected, it will fall right onto the passenger carpet!

To fix it, I used some rubber (silicone would've been better) hose to extend the factory vinyl tube to reach the metal pipe. I guess a better fix would be to replace the entire tube with a new one. On my late car, I was able to access it by removing the air vent. On an early dash, the air vent might not be big enough to fit your hand through, so my next idea would be to remove the glove box.