Sticking Fuel Filler Cover
6th March 2017
A month or so back I noticed that when I pushed the fuel filler cover to close it, it didn't pop back into the flush position. I'd have to tap on the cover a few times before it would pop back into position. My first thought was that something needed lubricating but then the flap moved freely once open so I decided that wasn't the problem. And the locking mechanism itself seemed to work smoothly. As it was wintertime and this hadn't caused me any problems, I didn't worry about it too much.
Then a few days ago I came across a few forum posts on this subject which made me think that this was a common problem. The sticking had apparently been so bad for some owners that they were unable to open their car's filler covers whilst at the filling station! Fixes ranged from having the entire filler cap assembly replaced under warranty to some people remaining convinced that a little lubrication was all that was required.
Then I read that there was a Service Bulletin from Volkswagen with a simple check and fix. Apparently the problem was due to a plastic rib on the inside of the filler flap rubbing on the interior. All you needed to do was check for signs of this rubbing and if found, shave the height of this rib by a millimetre or so in order to increase the clearance.
So I went back to look at my car. Sods Law as this time, the door opened and shut fine without sticking. However, on closer inspection I could see tiny marks where it looked to have been rubbing previously (see photos below). So I used a Stanley knife (apparently a file or sandpaper could also be used) and shaved less than a millimetre off the top of the plastic rib. Hopefully I will have no more problems.