Gilly, I also have this problem on my 03 E320, fuel refilling ALWAYS clicks off constantly! I have heard that it's probably my "vent" that's plugged up - something to do with vapor recovery (protecting the ozone) on the fuel pump handle (gas station pump).
So my question is... if there was a weight on this S-class' mechanism, where is the weight then... at the bottom of the gas tank?? I ask because in addition to the fuel refilling issue, I periodically get nothing when I give anything more than a quarter throttle (fuel pump & filter have been replaced, new plugs and wires, air filter good, used plenty of high quality injector/fuel system cleaner) and am probably "reaching" here but wondering if this weight might be in the bottom of my fuel tank plugging the line periodically!?
