I have the same problem of water ingress into the boot and rear passenger footwell ,have resealed the rear light but am now at a loss ,I'm about ready sell the piece of sh*t on and will never buy another but I would like to fix it both for the new owner and my own piece of mind ,any one got any good ideas ??
1 option is to remove everything from the boot and get someone in the boot with a flashlight. Use a hosepipe with medium pressure and spray over one area at a time covering the whole boot area/rear end. the person inside the car must have a look with the f/light where the leak is.
Hopes this help. We did it with my fathers ford focus and found the problem within 10 minutes.
REGARDS
Daniel Coetzee
May 2008
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