Advice Needed: Possible Water Leak on 1997 Riviera

Hi everyone, I am new to this form and a recent owner of a 1997 Riviera. I need advice on identifing a possible water leak in the trunk. If anyone has experienced a similar problem I would appreciate feedback. The symptoms are as follows, undercarpet insulation is damp and there is condensation on the underside of the spare tire cover. I have removed the carpets and can find no evidence of dampness on the walls of the trunk.

CdnRiv

take of the paneling in front of the taillights in the trunk, then, get a flashlight, your keyless entry transmitter, and a buddy, and get in your trunk(make sure your transmitter is on you, your buddy might get an idea if you dont!) Have your buddy squirt water at the taillights with a garden hose, preferably with a nozzle, and look around your taillight gaskets for incoming water.

That should be the only place it leaks from. When replacing the gaskets, be careful of the black sealer in them, wear some latex gloves, because it's a pain to get off of your skin.

Hi!
I have a water problem in my trunk as well. It´s a 95 Riviera and water seems to come from the left top corner of the trunk. I´ve been driving w/o the carpet for some weeks to locate the leak.
It drips from the screws that hold the lid, but thats not where water comes in.
Further to the front end (upper left) of the trunk there ist an opening with insulation material. This stuff is soaking wet! I wonder if water could run all the way from the sunroof...

Do you have a sunroof (astroroof)?

Thank you to everyone who advised me on the possible locations of the trunk water leaks. I have now fixed the problem - here is a summary.

After running the hose on the trunk lid with the carpets removed, I noticed that a puddle of water was forming just below the interior tailight assembly on the passenger side. Upon closer inspection, I noticed that the tailight assembly was not fully flush against the sheet metal. This could be a gasket, or a slightly missaligned part. I rectified the problem by applying a small bead of black automotive silicone on the area in question inside the trunk, and repeated the procedure on the outside. The silicone is not noticable and the leak in this area has stopped.

The second leak was a pinhole located under the trunk, passenger side, just above the hinge. I discovered this leak by accident. When I carefully inspected my trunk, I noticed that the passenger side interior supports near the wheelwell had rust on the seams from road-salt contaminated water flowing along them. The driver's side supports were rust-free and dry. The seams were preped using a rust converter, and repainted and sealed, and a small bead of clear silicone was applied to the pinhole underneath the trunk lid.

Thanks again for everyone's input

CdnRiv
Ontario, Canada
1997 Riviera

I have a 95, and there was a problem with water leaking in as well... It did look like it was coming from the seal or maybe the boat for the lid... but Actually! It was coming from the seal of the rear driver side window... it wasn't detected until rust started to bubble under the paint on the seem. It's not rusted from the rear of the rear drives side window to the corner of the trunk lid...

I had/have a leak in my 95 trunk too. It seems to come from underneath and mainly on the two little bolts that come up from the bottom on each side with the little plastic things on em. I think there may have been a more central leak also.

I'm big into car audio. During the winter I noticed condensation on my amplifier and other audio equipment. Not good :(. I've never noticed this in warm weather though. I recently stripped EVERYTHING out of the trunk and sprayed a visco-elastic sound deadener over the bare metal. Hopefully that will seal it up for next winter.