Flexible fuel vehicles

Important safety notes

Flexible fuel vehicles can be recognized by the sticker on the inside of the filler flap.

Flexible fuel vehicles can be operated with premium-grade unleaded gasoline and ethanol (E85) or a mixture of both. Ethanol fuel (E85) is a mixture of approximately 85% ethanol and 15% unleaded gasoline.

Ethanol fuel (E85) and its vapors are highly WARNING
Ethanol fuel (E85) and its vapors are highly flammable, poisonous and highly combustible. Ethanol fuel causes serious injury if it ignites, if it comes into contact with your skin or if you inhale the vapors. Avoid inhaling ethanol vapors and ethanol coming into contact with your skin. Before refueling, extinguish all naked flames. Never allow sparks or smoking materials near ethanol.

Changing the fuel type

For best performance and drivability, it is recommended that you use either one or the other fuel. Avoid alternating regularly between the two different types of fuel.
When changing between the fuel types, ensure that the following conditions are met:
- the fuel level is below half full.
- the fuel level is above the reserve level. This is identifiable by the fuel tank reserve warning lamp not being lit.
- you add more than 5 gallons (20 liters) of fuel.
- you switch off the engine before refueling.
- the engine is started and runs for at least five minutes immediately after refueling.

These precautions should prevent the possibility of engine difficulties arising from changing to a different fuel type.

If the engine still doesn't run correctly, refuel with at least 3 US gal (12 l) of premium-grade unleaded gasoline. This may improve the running of the engine.

Fuel consumption

Ethanol (E85) contains less energy per gallon than gasoline. To ensure that the engine performance with ethanol (E85) is similar to that when using gasoline, the engine must burn more ethanol. As a result, it is to be expected that fuel consumption will increase when using ethanol fuel (E85), compared to gasoline.

Maintenance

Inform your authorized Mercedes-Benz Center that you are operating or have operated the vehicle with ethanol (E85).

Low outside temperatures

Starting times may significantly increase at temperatures below 32 °F (0 °C ). At low outside temperatures, Mercedes-Benz recommends the use of an auxiliary heater.

For further information, consult an authorized Mercedes-Benz Center.

Rough idling may also be experienced at low outside temperatures until the engine is fully warmed up.

Ethanol (E85) is unsuitable for use if outside temperatures fall below 14 °F (-10 °C ).

High outside temperatures

At outside temperatures above 95 °F (35 °C ), the time required for the starting procedure may increase and be accompanied by rough idling following the start.

    See also:

    General information
    If you cannot lock or unlock the vehicle with the SmartKey, either the battery in the SmartKey is discharged, the SmartKey is faulty or the starter battery is discharged. ► Check the battery ...

    Switching on/off
    The three blue indicator lamps in the buttons indicate the ventilation level you have selected. If the battery voltage is too low, the seat ventilation may switch off. ► Make sure that ...

    CLS63 AMG
    Even more surprising is the fact that the high-performance AMG is a pretty good daily driver, too … considering it has 116 more horsepower, a firmer suspension, tighter steering and loud exhaust. ...