How Can I Stop My Trunk From Leaking When It Rains

I have 99 Saturn SC 3 Dr Coupe and I have a serious problem every time it rains the water gets into my trunk just recently I took out a bucket of water that was were my spare tire is held. The whole thing was filled to the tip with water I checked the body and there are no holes in it, and from what I can tell the trunk seal is in good condition. There is a vent or some kind of filter in my trunk on the drivers side under the tail light and this is where I believe the leak is coming from if anybody has my same model car and/or has any suggestions please let me know I would greatly appreciate it.

Well, this worked for my mom for several years, not sure it will for you but it may be worth a try. If you are parking downhill, park uphill, or vice versa. If that doesn't help, would it be worth putting a drain hole with a little one way valve there to let the water leave until you figure out a way to stop it from entering?

The weatherstripping ( rubber gasket or urethane ) around the rear window could be the problem . Have you checked it for tears ?

How Can I Stop My Trunk From Leaking When It Rains

Replace the weather strip molding.