The most common problem is OVERFILLING the fuel tank!
ONCE that has been done the fuel vapors (& raw fuel) will damage the charcoal filter (cannister) that is designed to absorb vapors durning refilling.

From your description that has happened to your car! I imagine you will need a new charcoal filter & shut-off valve.

MB part number for the charcoal filter is 202-470-12-89, list is $150

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator