I'm having the same problem on my '99 T4R. The leak is in the center front of the sunroof. It leaks when there's heavy rain or in a "touchless" carwash. The dealer said it's probably a leaky weather strip that surrounds the glass. He said it's about a 2 hour repair for which the charge would be about $164 + the part. His suggestion was to endure the leak (harmless, he maintains) until the spring. This would let it dry out AND, with warmer weather, allow the existing weather stripping to become softer and more pliable. He was really hinting (as much as a dealer service manager is able) that I do this myself. The main thing he said was to get the old stripping off clean.
