I'm sorry to say it is a big deal. The whole fuel tank needs to be replaced with the newer updated style.
It is about a 10-12 hour job and the fuel tank is very expensive.
I would just live with it and keep the tank full.
Mercedes never did a recall on this but dealerships were offering some assistance to customers that were good customers. For you, I think your just better leaving the issue alone. It won't ever hurt anything.
What is is like one piece of metal (baffle) loose? Did many years of the SL have problems with this? what years?
Yes, one large metal baffel is a little loose so it bows and makes noise. It doesn't slam around in the tank if thats what you think. Only 2003 models I think had this problem. I remember mercedes quickly addressing the issue and changing the tank part number on future production models. Its unfortunate this problem wasn't addressed under warranty or exhibited symptoms while it was under waranty.
so when the tank is more full it goes away.. okay.. next the door key. sometimes when i hold it down by the door the top goes down or goes up.. is there a reason this is intermiten>? or it only works if i don't touch the door keys for a few minutes ..like 10 minutes??
The key batteries might be getting low
Also, make sure you are holding the unlock or lock buttons down the entire time and pointing it at the drivers door handle.
The system works on direct line of sight from the key to the door handle. You have to be within 3 feet for reliable operation.