I have a 04 Jetta, and I have noticed a sound coming from the rear passenger area. How can I explain it, it happens when the car is off, and it is sitting in the garage.
You can hear it when everything is quiet, it is like a glunk, glunk glunk, like something is cycling. But everything is off and the key is out.

It happens only for a few seconds, every 30 seconds or so.

Its really strange, the VW dealer has no idea they can't hear it (so surprise there).
Anyone else heard of this? and if so what is it, so I can tell the dealer.

Your help is most appricated,
Thanks
Jeff