Fuel; Fuel Requirements - Subaru Impreza 2016 Owner's Manual

Fuel

CAUTION
Use of a fuel which is low in quality
or use of an inappropriate fuel
additive may cause damage to the
engine and/or fuel system.

Fuel requirements

The engine is designed to operate using
unleaded gasoline with an octane rating
of 87 AKI (90 RON) or higher.
Fuel octane rating
Using a gasoline with a lower octane
rating can cause persistent and heavy
knocking, which can damage the engine.
Do not be concerned if your vehicle
sometimes knocks lightly when you drive
up a hill or when you accelerate. Contact
your SUBARU dealer if you use a fuel with
the specified octane rating and your
vehicle knocks heavily or persistently.
RON
This octane rating is the Research Octane
Number.
AKI
This octane rating is the average of the
Research Octane and Motor Octane
numbers and is commonly referred to as
the Anti Knock Index (AKI).
Unleaded gasoline
The neck of the fuel filler pipe is designed
to accept only an unleaded gasoline filler
nozzle. Under no circumstances should
leaded gasoline be used because it will
damage the emission control system and
may impair driveability and fuel economy.
Gasoline for California-certified
LEV
If your vehicle was certified to California s
low emission vehicle (LEV) standards as
indicated on the underhood tune-up label,
it is designed to optimize engine and
emission performance with gasoline that
meets the clean burning low-sulfur Cali-
fornia gasoline specifications. If you live in
any other state than California, your
vehicle will operate on gasoline meeting
Federal specifications. Gasoline sold out-
side California is permitted to have higher
sulfur levels, which may affect the perfor-
mance of your vehicle s catalytic converter
and may produce a sulfur exhaust odor or
smell. SUBARU recommends that you try
a different brand of unleaded gasoline
having lower sulfur to determine if the
Starting and operating/Fuel
problem is fuel related before returning
your vehicle to an authorized dealer for
service.
MMT
Some gasoline contains an octane-en-
hancing additive called MMT (Methylcy-
clopentadienyl Manganese Tricarbonyl). If
you use such fuels, your emission control
system performance may deteriorate and
the CHECK ENGINE warning light/Mal-
function indicator light may turn on. If this
happens, return to your authorized
SUBARU Dealer for service. If it is
determined that the condition is caused
by the type of fuel used, repairs may not
be covered by your warranty.
Gasoline for cleaner air
Your use of gasoline with detergent
additives will help prevent deposits from
forming in your engine and fuel system.
This helps keep your engine in tune and
your emission control system working
properly, and is a way of doing your part
for cleaner air. If you continuously use a
high quality fuel with the proper detergent
and other additives, you should never
need to add any fuel system cleaning
agents to your fuel tank.
Many gasolines are now blended with
materials called oxygenates. Use of these
fuels can also help keep the air cleaner.
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