My cowl was pretty loose before i put new weather stripping in. The new weather stripping made for a much more solid fitment of the cowl and it doesn't move at all anymore. I suspect my windshield is original. I'm sure previous owners were troubleshooting the leak, as my trim pieces on the windshield have been removed. So they possibly made the leak worse trying to fix it unsuccessfully.My guess: Maybe leaks are more prevalent on vehicles that have had a windshield replacement where the cowl has been disturbed? I can't find any markings on my windshield, so I assume it was replaced by a prior owner. The windshield doesn't leak, but I suspect that the foam bits on the cowl, once compressed on the initial install, don't expand back out to their original thickness and leave small gaps. Total guess...