2007 Mercedes CLK-Class Owner's Manual - Page 314

Operation At the gas station Take off cap and set it in direction of arrow 2 in the recess on the fuel filler flap. To prevent fuel vapors from escaping into open air, fully insert filler nozzle unit. Only fill your tank until the filler nozzle unit cuts out - do not top up or overfill. Warning! G i Only use premium unleaded gasoline with a minimum Posted Octane Rating of 91 (average of 96 RON/86 MON). Information on gasoline quality can normally be found on the fuel pump. For more information on gasoline, see "Premium unleaded gasoline" ( page 475) or the Factory Approved Service Products pamphlet. Overfilling of the fuel tank may create pressure in the system which could cause a gas discharge. This could cause the gas to spray back out when removing the fuel pump nozzle, which could cause personal injury. i Leaving the engine running and the fuel cap open can cause the ú malfunction indicator lamp (USA only) or the ± malfunction indicator lamp (Canada only) to illuminate. More information can be found in the "Practical hints" section ( page 369). Replace fuel cap by turning it clockwise until it audibly engages. i Make sure to close the fuel filler flap before locking your vehicle as the flap locking pin prevents closing after you have locked the vehicle. Close fuel filler flap. 313