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GWarning
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gasoline
to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.
! Do not use diesel to refuel vehicles with a
gasoline engine. Even small amounts of the
wrong fuel result in damage to the fuel
system and engine.
! Do not switch on the ignition if you
accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel lines.
Notify a qualified specialist workshop and
have the fuel tank and fuel lines drained
completely.
Gasoline
Fuel grade
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
iOnly refuel with unleaded premium-grade
gasoline with a specified minimum octane
number of 91 (average value of 96 RON/
86 MON).
Usually you will find information about the
fuel grade on the pump. If you cannot find
the label on the gasoline pump, ask the gas
station staff.
You can find further information under
"Fuel" (Y page 335), by consulting an
authorized Mercedes-Benz Center or
visiting http://www.mbusa.com (USA
only).
Refueling
Fuel filler flap
The fuel filler flap is unlocked or locked
automatically when you open or close the
vehicle with the SmartKey or using KEYLESS-
GO.
The position of the fuel filler flap is to the rear
on the right. The position of the fuel filler cap
is displayed in the instrument cluster 8.
The arrow next to the gas pump indicates the
side of the vehicle.
Example: Coupe
:To open the fuel filler flap;To insert the fuel filler cap=Tire pressure table?Fuel type
Opening
XSwitch off the engine.
iWhen the engine is running and the fuel
filler flap is open, the ; engine
diagnostics warning lamp may light up.
For further information on warning and
indicator lamps in the instrument cluster,
see (Y page 245).
XRemove the SmartKey from the ignition
lock.
KEYLESS-GO: the driver's door is open.
This returns the ignition to position 0,
which corresponds to the SmartKey being
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removed. The driver's door can be closed
again.XPress the fuel filler flap in the direction of
arrow  :.
The fuel filler flap opens slightly.XOpen the fuel filler flap.XTurn the fuel filler cap counter-clockwise
and remove it.XInsert the fuel filler cap into the holder
bracket on the inside of filler flap  ;.XCompletely insert the filler neck of the fuel
pump nozzle into the tank and refuel.XOnly fill the tank until the pump nozzle
switches off.
!  Overfilling the fuel tank could damage the
fuel system.
Closing
XReplace the fuel filler cap and turn it
clockwise. The fuel filler cap audibly
engages.
i Close the fuel filler flap before locking the
vehicle. A locking pin otherwise prevents
the fuel filler flap from closing after the
vehicle has been locked.
XClose the fuel filler flap.164RefuelingDriving and parking
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Direct skin contact with fuels and the
inhalation of fuel vapors are damaging to your
health.
Premium-grade unleaded gasoline
!  To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline must be used.
If premium-grade unleaded gasoline is
unavailable and regular gasoline is used,
observe the following precautions:
R only fill the fuel tank to half full with
regular unleaded gasoline and add the
rest as soon as possible with premium-
grade unleaded gasoline.
R do not drive at the maximum speed.
R avoid sudden acceleration.
R when the vehicle is carrying a light cargo,
e.g. two passengers without luggage, do
not allow the engine to rev above
3000 rpm.
R when the vehicle is fully loaded or being
operated in mountainous terrain, do not
depress the accelerator pedal further
than  2
/ 3 of the pedal travel.
Fuel requirements
Use only premium-grade unleaded gasoline.
The octane number should be at least 91.
Details can be found on the gas pump. The
octane number is the average value of the
Research Octane Number (RON) and Motor
Octane Number (MON): (RON + MON) / 2,
also known as knock resistance.
Reformulated Gasoline (RFG) and/or
unleaded gasoline with additives can be used
if the concentration of the additives in the fuel
does not exceed 10%, e.g.:
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline
including other additives must not exceed 3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline can be used.
All of these mix fuels must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure
Additives in gasoline
One of the major problems in engine design
is the creation of carbon deposits during the
process of burning fuel. Mercedes-Benz
recommends that you use fuel brands that
have the additives which prevent the build up
of carbon deposits.
If you use fuels without these additives for a
longer period of time, there may be a build up
of carbon deposits, especially on the inlet
valves and in the combustion chamber.
This could lead to engine running problems,
e.g.:
R warm-up hesitation
R unstable idle
R knocking/pinging
R misfire
R power loss
In areas where carbon deposits may be
encountered due to lack of availability of
gasoline which contains these additives,
Mercedes-Benz recommends the use of
additives approved for use in Mercedes-Benz
vehicles.
Consult an authorized Mercedes-Benz Center
or visit  http://www.mbusa.com  (USA only)
to view a list of approved products. Observe
the instructions for use on the product label.
Do not mix other fuel additives with fuel. This
causes unnecessary costs and could damage
the engine.
336Service products and capacitiesTechnical data
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