when pumping gas the fuel backs out and the pump keeps clicking off. It takes about 20 minutes to pump a full tank
Mercedes-Benz Q&AAsk Your Question
2007 Mercedes-Benz S550 Question: why is my fuel backing up when pumping gas?
Answer #1milesauto from Miles Auto Service Inc., March 26, 2012, 11:11Master
Charcoal canister could be soaked with fuel. The "check engine" warning lamp could come on with this also. The canister can be taken off and drained by a technician. Its a good practice to stop putting fuel in tank when the nozzle clicks off the first time. If you keep trying to top off tank as much as you can, the fuel vapor system can get flooded.