Jeep Cherokee 2009 Operating Information Manual page 155

facturer recommends the use of gasolines that
meet the WWFC specifications if they are avail-
able.
Light spark knock at low engine speeds is not
harmful to your engine. However, continued heavy
spark knock at high speeds can cause damage
and should be reported to your dealer immedi-
ately. Engine damage resulting from operating
with a heavy spark knock may not be covered by
the new vehicle warranty.
Besides using unleaded gasoline with the proper
octane rating, gasolines that contain detergents,
corrosion and stability additives are recom-
mended. Using gasolines that have these addi-
tives may help improve fuel economy, reduce
emissions, and maintain vehicle performance.
Poor quality gasoline can cause problems such
as hard starting, stalling and stumble. If you
experience these problems, try another brand of
gasoline before considering service for the ve-
hicle.
METHANOL
(Methyl or Wood Alcohol) is used in a variety of
concentrations when blended with unleaded
gasoline. You may find fuels containing 3% or
more methanol along with other alcohols called
cosolvents.
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CAUTION!
DO NOT use gasolines containing Methanol or
E85 Ethanol. Use of these blends may result in
starting and driveability problems and may dam-
age critical fuel system components.
Problems that are the result of using methanol/
gasoline or E85 Ethanol blends are not the re-
sponsibility of the manufacturer and may not be
covered by the new vehicle warranty.
ETHANOL
The manufacturer recommends that your vehicle
be operated on fuel containing no more than 10%
ethanol.
Use of fuel with an ethanol content higher than
10% may result in engine malfunction, starting
and operating difficulties and materials degrada-
tion. These adverse effects could result in perma-
nent damage to your vehicle.
Purchasing your fuel from a reputable supplier
may reduce the risk of exceeding this 10% limit
and/or of receiving fuel with abnormal properties.
It should also be noted that an increase in fuel
consumption should be expected when using
ethanol-blended fuels, due to the lower energy
content of ethanol.
CAUTION!
Use of fuel with ethanol content higher than 10%
may result in engine malfunction, starting and
operating difficulties and materials degradation.
These adverse effects could result in permanent
damage to your vehicle.
CLEAN AIR GASOLINE
Many gasolines are now being blended that con-
tribute to cleaner air, especially in those areas
where air pollution levels are high. These new
blends provide a cleaner burning fuel and some
are referred to as "reformulated gasoline."
The manufacturer supports these efforts toward
cleaner air. You can help by using these blends as
they become available.
MATERIALS ADDED TO FUEL
Indiscriminate use of fuel system cleaning agents
should be avoided. Many of these materials in-
tended for gum and varnish removal may contain
active solvents or similar ingredients. These can
harm fuel system gasket and diaphragm materi-
als.