Mercedes-Benz 600 SEL 1993, Owner'S Manual

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Fuel Requirements
Use only Premium unleaded
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 number and the Motor (M)
octane number: [(R + M )/2 ]. This
is also known as ANTI-KNOCK
INDEX.
Unleaded gasoline containing
oxygenates such as Ethanol, I PA,
IBA and TBA can be used provid­
ed the ratio of any one of these
oxygenates to gasoline does not
exceed 10%, MTBE not to exceed
15%.
The ratio of Methanol to gasoline
must not exceed 3% plus addi­
tional 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
manufacturers is carbon build up
caused by gasoline. Mercedes-
Benz recommends to use only
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.
Do not blend other specific fuel
additives with fuel. They only
result in unnecessary cost, and
may be harmful to the engine
operation.
Damage or malfunctions resulting
from poor fuel quality or from
blending specific fuel additives are
not covered by the Mercedes-
Benz Limited Warranty.
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