I have a 98 honda civic si and recently the trunk started leaking really really bad!I took off weather stripping and it was extremly cracked and worn, so i went to auto wrecker and got weather stripping that was in much better shape, almost new looking, didnt help at all. I have been looking this problem up and I can see this year of civic is notorious for leaks in trunk. I see some people said that the sunroof drian hose could be disconected only problem is I dont know where that would be located. it seems onlt the right side of the trunk is leaking perhaps the tail light, but it seems to be dripping more from the top of the trunk then the light.
my car is a rebuild status with rear end damage but i have had it for three years and problem just started occuring.
any suggestions would be great im pretty much at a loss right now, car is going moldy and getting very gross on the inside. please help!

 

Pull everything out of the trunk. Floor, side carpet pieces, etc.

Pull the seats down, shut the trunk, and crawl back there through the front seat or whatever. Have a friend use a hose and slowly go around the car spraying water in. Once you see water, have your friend stop. Then re-create the leak until you trace it back to wherever it is coming from.

 

Before you waste all that time doing what cvcrcr99 said just pull back the side carpets in the trunk and see if your sunroof drain hoses are still connected. I had a 95 Si and both were disconnected when I bought it.