Today I discovered why my spare wheel was swimming in 30mm of water!
If anyone can explain why I should not permanently seal these vents would they please reply.
Thank you all.
As others have said its the rear vents...
However VW made newer versions with a rubber seal, instead of a foam seal (which degrades with age & lets water in)....You could buy the newer revised vents & it is possible to install from the inside without having to remove the outer bumper skin....
Discovered vent frames were fitted with rubber seals but they were worse than useless. So loose when I rattled them the noise could be heard on the other side of the road!
Solution;
Each flap removed, cleaned and replaced.
Sealed off two of the vents (see pic) using butyl and plastic cut from lids food container. Vent frame refitted using butyl seal.
Result; zero water ingress and NO noticeable effect with door or hatch closing.
Degraded seal on both Rear light clusters.
Solution;
Removed, replaced with butyl seal and refitted.
Result; zero water ingress over two heavy downpours.
Observations;
a) Each of the vents have a square area of apx 15" This despite there not being sufficient air space between the trim or the rear light access that would allow such a passage of air, even allowing for air pressure caused by door or hatch shutting.
b) Grommet below near side vents had been inserted upside down. Clearly an exterior a rectification.
c) Both vent pockets had been sealed with hot wax. Wax splatters on interior of all vent flaps. All wax was removed and the whole interior cavity was sprayed with liberal coats of silicone.
d) Vent flaps were not worn at all and did not require replacing (VW said they would) Saved £70+.
It is my opinion that the rear vents could be safely closed off completely.
My 5th VW and it will certainly be my last. Will go Japanese next.
TIP; do not be afraid of removing the bumper or the interior trim, just work slowly and ensure you know where all the metal clips are located. An old blanket protects the bumper when removed, an extra pair of hands helps to support the bumper while you removed the other end. Using grease or silicone on each clip eases reassembly immensely.
