2006 Mercedes CLS-Class Owner's Manual - Page 466

Technical data Fuels, coolants, lubricants etc. Premium unleaded gasoline ! Gasoline additives A major concern among engine manufacturers is carbon build-up caused by gasoline. Mercedes-Benz recommends only the use of quality gasoline containing additives that prevent the build-up of carbon deposits. After an extended period of using fuels without such additives, carbon deposits can build up especially on the intake valves and in the combustion area, leading to engine performance problems such as: Warm-up hesitation Unstable idle Knocking/pinging Misfire Power loss Warning! G Gasoline is highly flammable and poisonous. It burns violently and can cause serious injury. Whenever you are around gasoline, avoid inhaling fumes and skin contact, extinguish all smoking materials. Never allow sparks, flame or smoking materials near gasoline! To maintain the engine's durability and performance, premium unleaded gasoline must be used. If premium unleaded gasoline is not available and low octane fuel is used, follow these precautions: Have the fuel tank only partially filled with unleaded regular and fill up with premium unleaded as soon as possible Avoid full throttle driving and abrupt acceleration Do not exceed an engine speed of 3000 rpm if the vehicle is loaded with a light load such as two persons and no luggage Do not exceed /3 of maximum accelerator pedal position if the vehicle is fully loaded or operating in mountainous terrain 2 465