Maintenance and Car Care 269
Fuel Recommendations
Your Porsche is equipped with catalytic conver-
ters and must use UNLEADED FUEL ONLY.
Your engine is designed to provide optimum
performance and fuel economy using unleaded
premium fuel with an octane rating of 98 RON
(93 CLC or AKI). Porsche therefore recom-
mends the use of these fuels in your vehicle.
Porsche also recognizes that these fuels may not
always be available. Be assured that your vehicle
will operate properly on unleaded premium fuels
with octane numbers of at least 95 RON
(90 CLC or AKI), since the engine's “Electronic
Octane™ knock control” will adapt the ignition
timing, if necessary.
It is important to observe the regular service inter-
vals, and particularly the oil change intervals, spe-
cified in your Maintenance Schedule.
The use of UNLEADED FUEL ONLY is critically
important to the life of the catalytic
converters. Deposits from leaded fuels will
ruin the converters and make it ineffective
as an emission control device.
Cars with catalytic converters have a smaller fuel
tank opening, and gas station pumps have smaller
nozzles. This will prevent accidental pumping of
leaded fuel into cars with catalytic converters.
Unleaded fuels may not be available outside the
continental U.S. and Canada. Therefore, we
recommend you do not take your car to areas or
countries where unleaded fuel may not be
available.
Octane ratings
Octane rating indicates a fuel's ability to resist
detonation. Therefore, buying the correct octane
gas is important to prevent engine “damage”.
The RON octane rating is based on the research
method. The CLC (U.S. Cost of Living Council oc-
tane rating) or AKI (antiknock index) octane rating
usually displayed on U.S. fuel pumps is calculated
as research octane number plus motor octane
number, divided by 2, that is written as:
The CLC or AKI octane rating is usually lower than
the RON rating:
For example: 95 RON corresponds 90 CLC or
“AKI”
f Do not use fuel additives without Porsche
approval.
Fuels containing ethanol
f Do not use any fuels containing more than 10
percent ethanol by volume.
We recommend, however, to change to a different
fuel or station if any of the following problems
occur with your vehicle:
– Deterioration of driveability and performance.
– Substantially reduced fuel economy.
– Vapor lock and non-start problems, especially
at high altitude or at high temperature.
– Engine malfunction or stalling.
RON MON+
2
----------------------------------
or
RM+
2
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