98Oldsvan leaky roof

Newbie here - first post.
I have a 98 olds silhouette minivan that, despite the typical problems has been a fairly reliable machine. The latest trouble has me stumped. When it rains, I get a leak from the overhead temp/mileage display unit. I pulled it down (4 screws) and found that the headliner is wet. The leak is getting progressively worse - initially it was just a drip, now it is turrning into a stream. I did a visual inspection and can't see the leak. With the luggage rack and the no-drip edges to the roof, I'm guessing the leak could be anywhere.

Anyone have this problem before? I thought maybe someone could give me a place to start. Any help would be appreciated. Thanks.

Try these links for more info:
http://www.automotiveforums.com/vbulletin/showthread.php?t=349212
http://www.automotiveforums.com/vbulletin/showthread.php?t=276515
http://www.automotiveforums.com/vbulletin/showthread.php?t=476782
http://www.automotiveforums.com/vbulletin/showthread.php?t=340125

it is leaking at the top of the windshield molding[the black rubber strip that goes around the windshield.] unless you want to pull the windshield out and re neoprene the gap between the body and the molding. mine had a small gap at the top on passengerside where the genious that had put the windshield in didnot put enough neoprene in to fill the gap good enough. i put a bead of neoprene across the top of the molding and down each side two inches [ being careful not to block the drain valley that runs down each side of the molding] and it has not leaked since. you can buy a small tube instead of a caulk gun size.
good luck

Thanks for the responses. I'll go after the top seal at the windshield first, then the door seals. If those don't dry things up, I'll go after the luggage rack bolts. Thanks again.

Mine started leaking on the passenger side top just past the center of the windshield. The area surrounding it was also rusting, which contributed to the leak. I remember taking off from a stop and getting doused with cold water from the center area where the interior lights were located... not fun.

98 0lds sil, on top of the windshield where the molding meets the top of the van put a bead of neoprene all the way across from one side to the other now on the side of the molding you have to leave the water valley open. if you look at the top there is a drain groove that runs toward the molding then down toward the cowl. you can put a smooth bead from the bead you put on the top down both sides of the molding 1" or so . what's making it leak is the molding acts like a dam as the water comes off the top. if there is a gap in the neoprene that was used to seal the windshield then the water will come in and come out of the dic console in the roof.mine you could look at the windshield from the inside with a good flashlight and you could see where the dumb*** did not use enough neoprene to seal the molding to the van top.i don't think its leaking from the roof racks.it took a while to find where mine was leaking . the glass doesn't seal to the metal the rubber molding goes around the windshield then they seal theopening then drop the windshield with the molding on it in. good luck