I'm having the same symptoms as others have reported on MBWorld whereby whenever I fill my 2007 CLK 350, I smell gas for a few days. Once the tank is about 3/4 full or less, no smell.

Took it into the dealership and they said the fuel tank pressure sensor has gone bad. I'm thinking fine since I bought the extended Premium Plus Warranty from National. Turns out National is not covering it because it's part of the "emissions system". Does that make sense? Sound like a reasonable thing for an extended warranty provider to turn down? I was disappointed because that's exactly what I bought the warranty after I bought the car used... no idea what ticky tack thing might go wrong with it.

It's worth having the dealership or a qualified indie shop do this....... I tried to fix my gas tank seal leak myself.... and was unsuccessful.... there is some special skill to get it to seal correctly..... and the consequences of a bad seal and the right ignition source is not so good

GL.

Yep, I'm cool with the dealer doing it. Just thought it seemed like something that a warranty should cover.

The fuel sensors are not part of the emissions system. They are connected to the EECS system. Damn extended warranty providers!

Doesn't EECS stand for "evaporate emissions control system" though? I think that's their logic.