Jeep GRAND CHEROKEE L 2023, Owner'S Manual

Page: 401 / 424

TECHNICAL SPECIFICATIONS 399
(Continued)
M
ETHYLCYCLOPENTADIENYL
M
ANGANESE
T
RICARBONYL
(MMT) I
N
G
ASOLINE
MMT is a manganese-containing metallic additive
that is blended into some gasolines to increase
octane. Gasoline blended with MMT provides no
performance advantage beyond gasoline of the
same octane number without MMT. Gasoline
blended with MMT reduces spark plug life and
reduces emissions system performance in some
vehicles. The manufacturer recommends that
gasoline without MMT be used in your vehicle. The
MMT content of gasoline may not be indicated on
the gasoline pump; therefore, you should ask your
gasoline retailer whether the gasoline contains
MMT. MMT is prohibited in Federal and California
reformulated gasoline.
F
UEL
S
YSTEM
C
AUTIONS
NOTE:
Intentional tampering with the emissions control
system can result in civil penalties being assessed
against you.
CAUTION!
Follow these guidelines to maintain your
vehicle’s performance:

The use of leaded gasoline is prohibited by
Federal law. Using leaded gasoline can impair
engine performance and damage the emis -
sions control system.

An out-of-tune engine or certain fuel or ignition
malfunctions can cause the catalytic
converter to overheat. If you notice a pungent
burning odor or some light smoke, your engine
may be out of tune or malfunctioning and may
require immediate service. Contact an autho -
rized dealer for service assistance.

The use of fuel additives, which are now being
sold as octane enhancers, is not recom -
mended. Most of these products contain high
concentrations of methanol. Fuel system
damage or vehicle performance problems
resulting from the use of such fuels or addi -
tives is not the responsibility of the manufac -
turer and may void or not be covered under
the New Vehicle Limited Warranty.
CAUTION!
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23_WL_OM_EN_USC_t.book Page 399