Mercedes Benz 2003 e 320 User Manual

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Technical data
Fuels, coolants, lubricants etc.
Premium unleaded gasoline
Fuel requirements
Use only premium unleaded gasoline 
meeting ASTM standard D 439:
The octane number (posted at the 
pump) must be 91 min. It is an average 
of both the Research (R) Octane Num-
ber and the Motor (M) Octane Number: 
(R+M)/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 is not to 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.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the 
use of quality gasoline containing additives 
that prevent the build-up of carbon depos-
its.
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 en-
gine performance problems such as:
Warm-up hesitation
Unstable idle
Knocking/pinging
Misfire
Power loss
Do not blend any specific fuel additives 
with fuel. This only results in unnecessary 
costs and may be harmful to the engine op-
eration.
!
To maintain the engine’s durability and 
performance, premium unleaded gaso-
line 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 per-
sons and no luggage
Do not exceed 2/3 of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in 
mountainous terrain