2005 vdp
Opened the sunroof and noticed the rear headliner flapping slightly and feel it could be the start of something.
Any suggestions on a fix.
Many thanks for any suggestions....

 

It will only get worse. If you have the funds pay to have it repaired and make sure you have the sunroof done at the same time. If you don't have the funds and it really bothers you it is not that bad a job. It sucks, but it is not that bad to remove the headliner (there are plenty of threads on it on this forum), clean it carefully and recover with new material. JoAnne Fabrics has a gray that works pretty well color wise. I did this on my Range Rover. Again make sure to do the sunroof at the same time. I had mine done by a professional on the side, but she didn't do the sunroof and it is failing. $250 is what she charged me with material. Prices range from $200 to $1000 from what I am seeing.

Now if you want to just get by then use some clear silicon and glue it up. Maybe you can get to the failing spot from the sunroof area or from the side. It will not look great, but it will not hit your head. I did this with the sunroof. you can cut the material if you have no access, it will look bad, but you can live with it. As you will have to have it redone in the end, it buys you time and the material will come out anyway. So no harm no foul and you have a solution. DO NOT CUT THE ACTUAL HEADLINER BOARD - just cut the covering.

As the car ages the headliner glue stays stuck, but the foam pad between the material and the glue starts to fall apart. It doesn't stop. Gluing it up will help for the short term, but if you open the sunroof the wind will accelerate the breakdown. Almost all cars have the same problem.

 

Leave the sun roof cover open, the sun roof itself, and all the windows CLOSED while moving.
That is what i'm doing with mine, to put as little stress on the fabric as possible.
Parking in the garage when not in use.
Avoiding hot temperature spikes, from setting in the sun, helps out too.