Mercedes-Benz 2008 CLS-Class Automobile User Manual


 
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Technical data
Fuels, coolants, lubricants etc.
Premium unleaded gasoline Fuel requirements
Only use premium unleaded fuel:
ț The octane number (posted at the
pump) must be 91 min. It is an average
of both the Research Octane Number
(RON) and the Motor Octane Number
(MON): (RON+MON)/2. This is also
known as the ANTI-KNOCK INDEX.
Unleaded gasoline containing oxygenates
such as ethanol, IPA, IBA and TBA can be
used provided the ratio of any one of these
oxygenates to gasoline does not
exceed 10%; MTBE must not exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using mixtures of ethanol and methanol is
not allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc.
Warning! G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious per-
sonal injury.
Never allow sparks, flame or smoking mate-
rials near gasoline!
Turn off the engine before refueling.
Whenever you are around gasoline, avoid in-
haling fumes and skin or clothing contact,
extinguish all smoking materials.
Direct skin contact with fuels and the inha-
lation of fuel vapors can damage your
health.
!
To maintain the engine’s durability and per-
formance, premium unleaded gasoline must be
used. If premium unleaded gasoline is not avail-
able and low octane fuel is used, follow these
precautions:
ț Have the fuel tank only partially filled with
unleaded regular gasoline and fill up with
premium unleaded gasoline as soon as pos-
sible.
ț Avoid full throttle driving and abrupt acceler-
ation.
ț 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.
ț Do not exceed
2
/
3
of maximum accelerator
pedal position if the vehicle is fully loaded or
operating in mountainous terrain.