So your trunk lid makes noise and rattles on bumps you say?
Well I found this old TSB today while I was cleaning out my junk drawer and thought I would post it on here to help peeps out.
Date: June 15, 2000
Models: New Beetle
Subject:Trunk Lid, Eliminating Wind Noise or Rattles.
Condition: WInd noise or rattles coming from trunk lid.
For Service Technitions
May be caused by tension screw not making contact on plastic stops.
with trunk lid closed set screw must make contact with the plastic stop with enough preload to prevent rattling.
Check preload tension by placing a slip of paper over the plastic stop and carefully closing the trunk lid.
pull on the paper (paper should notslide out)
If paper slides out adjust the tensioners as follows
1. turn set screw out in small increments untill it makes enough contac to prevent paper from sliding out.
NOTE: these are the scissor like things at the top of the trunk lid the adjuster screw is the one that makes contact with the black plastic stopper in the middle of the scissors.
I hope that this helps.
Tom aka Fowvay