So I think I know what the problem is this time but I already screwed up once and I just want to make sure.

The Problem: Whenever it would rain the passanger floor board would be damp, nothing much but I couldn't stand it. So I tore the carpet up and discovered that one of the seams had rotted away up where your feet are. I punched it out and got a hole about 1.5 in tall and 5 in long. I then patched the hole with fiberglass from both the inside and the other side which was in the wheel well. (see pics) After the fiberglass was dry I tested with a hose and was suprised to see that it was now leaking worse than before.

The Solution: This is what I need confirmation on, I think I know how the drainage system works but I can't really see through the car so I'm just guessing.

It didnt take me long to realize that no water ran down the wheel well side of the patch, nor did any run down the floor side yet water still dripped out both sides. After looking under the hood next to the heater core I realized that there is some sort of drainage channel where water from the windshield drips. I therorized that the bottom of the channel makes a "V" kind of shape right above the wheel well. So when I put the patch on I was really patching the bottom of the channel but I didn't know that at the time. So now the water is getting caught in between the two patches and leaking through on both sides. (see my diagram)

So would removing the current patch and trying to seal the bottom of that channel fix it? Or am I just imagining things and theres a totally different way that the water drains down? Would very much appreciate if someone could help.

 

The area under the heater box in the engine comparatment is a very common spot to rot out. Leaves and dirt get in there and hold moisture, causing rust. Same thing goes with the area under the wipers. Atleast that area has a screen over it to keep the big stuff out. The picture of the fiberglass in the wheel well is the area I'm talking about.

It looks like the inside of the car isn't as bad. Although looks like the floor pannel is starting to go where it meets the kick pannel. If you pull that padding off the firewall, you might find some more rust.

I believe there is a drain hole for the channel around the wipers. It can't be that big if there is one though. It think it routes the water to the bottom of the fenders infront of the door.

The correct way to fix the problem would be to cut out the bad stuff and weld in some new metal.