Page 228 of 368

Black plate (42,1)Buick Encore Owner Manual - 2013 - crc - 1/8/13
9-42 Driving and Operating
Fuel
Use of the recommended fuel is an
important part of the proper
maintenance of this vehicle. To help
keep the engine clean and maintain
optimum vehicle performance, we
recommend the use of gasoline
advertised as TOP TIER Detergent
Gasoline.
Look for the TOP TIER label on the
fuel pump to ensure gasoline meets
enhanced detergency standards
developed by auto companies. A list
of marketers providing TOP TIER
Detergent Gasoline can be found at
www.toptiergas.com. TOP TIER
gasoline is only available in the U.S.
and Canada.
Recommended Fuel
Use regular unleaded gasoline with
a posted octane rating of 87 or
higher. If the octane rating is less
than 87, an audible knocking noise
may be heard. If this occurs, use a
gasoline rated at 87 octane or
higher as soon as possible. If heavy
knocking is heard when using a
higher octane rated gasoline, the
engine needs service.Prohibited Fuels
Gasolines containing oxygenates,
such as ethers and ethanol, as well
as reformulated gasolines are
available in some cities. If these
gasolines comply with the
previously described specification,
then they are acceptable to use.
However, E85 (85% ethanol) and
other fuels containing more than
15% ethanol must be used only in
flex fuel vehicles.{CAUTION
Do not use fuel containing
methanol. It can corrode metal
parts in the fuel system and also
damage plastic and rubber parts.
That damage would not be
covered under the vehicle
warranty.
Some gasolines that are not
reformulated for low emissions can
contain an octane-enhancing
additive called
Page 229 of 368

Black plate (43,1)Buick Encore Owner Manual - 2013 - crc - 1/8/13
Driving and Operating 9-43
methylcyclopentadienyl manganese
tricarbonyl (MMT). Do not use
gasolines with MMT as they can
reduce spark plug life and affect
emission control system
performance. The malfunction
indicator lamp may turn on. If this
occurs, see your dealer for service.
Gasoline Specifications
At a minimum, gasoline should meet
ASTM specification D 4814. Some
gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. See“Prohibited
Fuels" in Recommended Fuel on
page 9-42.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
vehicle may not pass a smog-check
test. See
Malfunction Indicator
Lamp on page 5-14. If this occurs,
return to your authorized dealer for
diagnosis. If it is determined that the
condition is caused by the type of
fuel used, repairs may not be
covered by the vehicle warranty.
Fuels in Foreign
Countries
If planning to drive in countries
outside the U.S. or Canada, the
proper fuel might be hard to find.
Check regional auto club or fuel
retail brand websites for availability
in the country where driving. Never
use leaded gasoline, fuel containing
methanol, or any other fuel not recommended. Costly repairs
caused by use of improper fuel
would not be covered by the vehicle
warranty.
Fuel Additives
To provide cleaner air, all gasolines
in the United States are now
required to contain additives that
help prevent engine and fuel system
deposits from forming, allowing the
emission control system to work
properly. In most cases, nothing
should have to be added to the fuel.
However, some gasolines contain
only the minimum amount of
additive required to meet U.S.
Environmental Protection Agency
regulations. To help keep fuel
injectors and intake valves clean
and avoid problems due to dirty
injectors or valves, look for gasoline
that is advertised as TOP TIER
Detergent Gasoline. Look for the
TOP TIER label on the fuel pump to
ensure gasoline meets enhanced
detergency standards developed by
the auto companies. A list of
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Black plate (44,1)Buick Encore Owner Manual - 2013 - crc - 1/8/13
9-44 Driving and Operating
marketers providing TOP TIER
Detergent Gasoline can be found at
www.toptiergas.com.
For customers who do not use TOP
TIER Detergent Gasoline regularly,
one bottle of Fuel System Treatment
PLUS, part number 88861013,
added to the fuel tank at every
engine oil change, can help clean
deposits from fuel injectors and
intake valves. GM Fuel System
Treatment PLUS is the only
gasoline additive recommended by
General Motors. It is available at
your dealer.
Gasolines containing oxygenates,
such as ethers and ethanol, and
reformulated gasolines might be
available in your area. We
recommend that you use these
gasolines, if they comply with the
specifications described earlier.
However, E85 (85% ethanol) and
other fuels containing more than
15% ethanol must not be used in
vehicles that were not designed for
those fuels.Notice:
This vehicle was not
designed for fuel that contains
methanol. Do not use fuel
containing methanol. It can
corrode metal parts in the fuel
system and also damage plastic
and rubber parts. That damage
would not be covered under the
vehicle warranty.
Some gasolines that are not
reformulated for low emissions can
contain an octane-enhancing
additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant
where you buy gasoline whether the
fuel contains MMT. We recommend
against the use of such gasolines.
Fuels containing MMT can reduce
spark plug life and affect emission
control system performance. The
malfunction indicator lamp might
turn on. If this occurs, return to your
dealer for service.Filling the Tank
{WARNING
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
.To help avoid injuries to you
and others, read and follow
all the instructions on the fuel
pump island.
.Turn off the engine when
refueling.
.Keep sparks, flames, and
smoking materials away
from fuel.
.Do not leave the fuel pump
unattended.
.Do not reenter the vehicle
while pumping fuel.
.Keep children away from the
fuel pump and never let
children pump fuel.
(Continued)