I have a 2006 mustang GT and water leaks from firewall when it rains, I have removed the drain hole grommets and seam sealed every thing I can reach and replaced cowl clips and sealed them. I slowed down the leak but can't figure out how to stop it, I've tried a smoke machine and I don't see any smoke in the area. Has anyone else had this issue? Where did you find the leak? My floor is rusting, I need this fixed asap! Thanks

 

I had to have both my fenders pulled and have the seams sealed.

 

I guess I'll be taking my fender off, can't hurt to reseal it.

 

Mine was leaking on the passenger side, it was at the seam so I knew needed to be sealed and it did fixed it. I also did the driver side, even though I don't think it was leaking, but as you can see it was probably just a matter of time.

 

I think I got the leak fixed I took carpet out only to find the passenger side has been leaking apparently for a long time there was standing water in the floor, the top of carpet was dry and car never smelled musty and damp but the floor is rusted and I have to find the leak all over again😫.

 

Did you seal around the harness that goes through the firewall on the passenger side? That was I believe a recall or TBS

 

I have not sealed around harness, I was scraping rust off floor pan and popped off a plug in the front left of passenger side. I ran water over windshield to see where leak is coming from and saw water running like a river under the plug. Why would water run under floor pan? It does it on both sides of car like it was designed with a channel under floor.