Hi All,
I'm hoping someone can give me some good advice or tips on a problem I'm having with condensation in the spare wheel well on my Skoda Superb (saloon 170 DSG).
For the last few months (since autumn / winter basically) I've noticed that I'm regularly getting condensation at the top of the spare wheel well (at the back, closest to the rear seats). Initially I thought I had a leak into the car, because I was getting severe condensation build-up on the inside of the front and rear windows whenever there was a cold / frosty night (the condensation was literally freezing on the inside of the windows). I checked everything I could think of, but couldn't find a leak. Then I discovered that I had a considerable amount of water in the spare wheel well (maybe a litre or so). I took the water out, dried the well and waited to see what happened. Lo and behold, the condensation inside the windows issue went away overnight. Happy days I thought.
When I discovered the water in the wheel well, I checked the carpets all around the boot and was surprised that they were bone dry. There was small amount of ice on the underside of the carpet liner (the removable carpet) that I defrosted and dried out. The rest of the metal surfaces were dry and I couldn't see any leaks or holes. The plastic boot liner was also dry. So I was a bit stumped, but I figured I'd wait and see what happened. And what has happened is that, every night that the air temperature is cold (below 5c or so), I get a small amount of condensation in the spare wheel well again. It's always in the same place - towards the top and back of the well. My best guess is that this has been happening for quite some time and the build-up of water in the well happened over a year or so, rather than through a leak or water ingress. I've checked all around the boot again and still can't find any leaks. Also, I have driven the car in wet weather, and checked it after heavy rain, and there isn't any water getting into the boot after these events. It always seems to be after a cold night. Hence my conviction that it is condensation rather than a leak.
So what do I do now? Do I just wipe off the condensation every week or so and put up with it? Should I put a dehumidifier bag in the well or something? Or am I missing something obvious? When I was looking in the boot just now, I noticed that there are two rubber grommets / bungs at the top of the well, close to where the condensation is happening. When I levered these up, I was surprised to discover that I was basically looking down at the tarmac! I'm not sure what I expected to see (other than a recess or insulation maybe), but they are basically just holes onto the road. So is it just that the rubber on the bungs has shrunk / perished over the years (the car is 13 years old almost)? And, if so, can I buy new bungs or should I just tape over them or use sealant around them or something? I'm not entirely sure what purpose they are serving, but I don't want to mess with them if they're doing something important! (As in, if they are designed to aid circulation in the boot, I don't to seal them and stop air circulation).
I should add that I have searched for the issue on here, but it mostly seems to affect Octavias, and the problems mostly don't seem to apply to me: there isn't a rear washer to leak, water seems to be draining as normal from the rear of the car, there aren't any signs of water ingress etc.
I know it will be much less of an issue over the coming months (and will be hard to prove that any intervention has worked until the nights get cold again), but I'm hoping someone can point me in the right direction.
Many thanks,
Declan.