2008 Mercedes CL-Class Owner's Manual - Page 552

Operation At the gas station Take off the fuel filler cap and set it in the direction of arrow 2 and place it into holder 3 located on the inside of 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 off or overfill. Warning! G i Only use premium unleaded gasoline with a minimum Posted Octane Rating of 91 (average of both the Research Octane Number (RON) and the Motor Octane Number (MON): (96 RON+86 MON)/2. Information on gasoline quality can normally be found on the fuel pump. Please contact gas station personnel in case labels on the fuel pump cannot be found. For more information on gasoline, see "Premium unleaded gasoline" ( page 737), see "Fuel requirements" ( page 737), and the Factory Approved Service Products pamphlet (USA only) in your vehicle literature portfolio, or contact an authorized Mercedes-Benz Center. 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. Replace the 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 the fuel filler flap. You should hear the latch close shut. i Leaving the engine running and the fuel cap open can cause the yellow engine malfunction indicator lamp ± to illuminate. For more information, see the "Practical hints" section ( page 612). 551