I have a SLK320 which I acquired a few months ago. The car has been great so far expect when I have to fill the car at the gas station. The problem I have is that the fuel pump at the gas station stops every second. It takes me about 20 minutes to fill up the tank since the pump keep shutting all the time. I have tried to keep the nozzle out a little when filling but no success. Even at the smallest fuel flow from the fuel pump it keep shutting. I have tried different gas stations and no luck. It is unbelievable and I can not figure out what could be the problem.
I need to mention though that all this time I have had this problem at every fill up expect two times that I was able to fill the car completely without the fuel pump shutting off all the time. I can not explain how and why that happened or what caused it to work those times.

Please if you have any ideas share. I can work on these cars myself to some extend.