I have noticed that when I close the door on my car that there is a rattle noise from the rear bumper.

This is only when all the other doors & windows are closed, the noise sounds like a flap opening & closing, it comes from both sides of the rear of the car.

My question is: does anyone know if there is a pressure relief flap in the rear quarter panels ?, I know some cars have them to relieve the build up of air to aid door closing.

If not, off to the dealers I go :wonder:

I think there is at least 1 pressure equalising flap in the rear of the car, somewhere around the rear bumper I think. Both of my Mk2 Octavias have done it.

I think it also facilitates good airflow through the car as well.