So I recently noticed some water entering the spare wheel area in the trunk. I did some diagnostics and noticed that the water was actually coming in from the trunk seal. The water was getting underneath it and trickling down the back end of the trunk and into the spare wheel bay area. Fortunately there wasnt much water, but any water leak = NO.
I remember having a similar problem with my E36 BMW which I successfully fixed without the need to buy any parts.
So here is the fix and a question:
I removed the interior trim pieces that interefered with the rubber seal, then pulled the rear part of the seal upwards upto the the light area. I then proceeded in crimping the edge of the seal rubber seal using some pliers ( whilst off the car!) bit by bit to create a tighter seal. I used a rubber mallet to refit the seal. No leaks at all thus far!
Does anyone know what that seal type of grease is that is supposed to be smeared on the edge of the trunk lip before installing the rubber seal? They use this at the factory for edges that have rubber seals seated on them to prevent moisture build up and help againt water ingestion. Thanks.

 

I lied I didnt fix it, noticed a slight puddle when I removed the spare wheel again a couple of days ago.

Heres the strange thing, been driving around now for the last 3-4 days in heavy rain and no leaks. I dont have the interior trim panels in place either. I am thinking that as soon as I put the trim panel back in the leak will re-appear. ?