Hi
I have a 1989 190E 2litre but have a recurring problem I can't seem to
find how it happens But after any rain the rear passenger side seat belt
is soaking wet whenever the belt is used

I have tried to see it the Roof panel channels are blocked but can't see
a drain but if I poured down the side of the track and appears to be
coming out below the car near the rear tyre

Also there is wet in the boot again no evidence of holes etc

Is this a common problem or uniquely mine