Mercedes Benz 2007 r 320 cdi User Manual

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Technical data
Fuels, coolants, lubricants, etc.
Gasoline additives (gasoline engine)
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 engine performance problems such as:
Warm-up hesitation
Unstable idle
Knocking/pinging
Misfire
Power loss
In areas where carbon deposits may be 
encountered due to lack of availability of 
gasolines which contain these additives, 
Mercedes-Benz recommends the use of 
additives approved by us for use on 
Mercedes-Benz vehicles. Refer to Factory 
Approved Service Products pamphlet for a 
listing of approved product(s). Follow 
directions on product label.
Do not blend other specific fuel additives 
with fuel. This only results in unnecessary 
costs and may be harmful to the engine 
operation.
Damage or malfunction resulting from 
poor fuel quality or from blending addition-
al fuel additives other than those tested 
and approved by us for use on 
Mercedes-Benz vehicles listed in the Fac-
tory Approved Service Products pamphlet 
are not covered by the Mercedes-Benz 
Limited Warranty.
Fuel requirements
Gasoline engine
Only use premium unleaded fuel.
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 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.