I have an older Volkswagen that I love dearly, but lately I've been noticing a lot of wind noise on the highway and occasional water leak in heavy rain or a car wash. The problem appears to be the weatherstripping. How do I fix it? – Georges
I've had the same problem myself with a Golf that is now a decade old. It started several years ago and has progressively gotten worse.
The first thing to do is locate the source of the leak. Since water can move and, with the help of gravity, find the path of least resistance, locating water leaks can be a little tricky. The wind leak might be your best bet in narrowing your search.
There are two likely areas. The first will be the more solid system in the window track, most likely with a "feathered" edge to allow the window to slide up and down. This strip contains a slot for the glass and should fit snugly within a channel in the frame surrounding the window.
The other spot to look is around the perimeter of the door itself, where you will find a rather soft and complex rubber weather strip that circles the entire door. If it comes loose from the door, it can cause the wind or air leak you describe.
It is also possible that if your car is old enough and that seal has not been lubricated regularly that it has dried up, cracked or otherwise become compromised. Squeeze this material and it should feel soft and bounce back to its original shape quickly.
As with most car problems, there are two solutions – repair or replace. The repair involves finding the offending area and, provided it is still in good shape, pushing or gluing it back in place with the proper adhesive. If there are cracks or similar issues, you might be lucky and be able to repair them. Hopefully this will work as the factory replacement seal is expensive.
Aftermarket parts are available for some more popular vehicles, so it is worth checking these out. You might also be able to find a wrecked car of the same make and model and salvage a piece of weatherstripping from it. If you are replacing the seal or part of it, make sure you thoroughly clean the areas where the weatherstripping is fastened in order to ensure a good seal.