Subaru 2006 Legacy - Manual (Page 241)

7-2
Starting and operating
Starting and operating
Fuel
„ Fuel requirements
T 2.5-liter non-turbo models
The 2.5-liter non-turbo engine is designed
to operate using unleaded gasoline with
an octane rating of 87 AKI or higher.
T 2.5-liter turbo models and 3.0-liter
models
The 2.5-liter turbo engine and 3.0-liter en-
gine are designed to operate using premi-
um unleaded gasoline with an octane rat-
ing of 91 AKI or higher. If premium unlead-
ed gasoline is not available, regular un-
leaded gasoline with an octane rating of
87 AKI or higher may be temporarily used.
For optimum engine performance and
driveability, it is required (for 2.5-liter turbo
models), and recommended (for 3.0-liter
models) that you use premium grade un-
leaded gasoline.
NOTE
Be sure to use premium unleaded gas-
oline of 91 AKI or higher for a 2.5-liter
turbo engine model. If other gasoline
(lower than 91 AKI) is used, knocking,
reduced output and poor accelerator
response will result.
T Fuel octane rating
This octane rating is the average of the
Research Octane and Motor Octane num-
bers and is commonly referred to as the
Anti Knock Index (AKI).
Using a gasoline with a lower octane rat-
ing can cause persistent and heavy
knocking, which can damage the engine.
Do not be concerned if your vehicle some-
times knocks lightly when you drive up a
hill or when you accelerate. See your
dealer or a qualified service technician if
you use a fuel with the specified octane
rating and your vehicle knocks heavily or
persistently.
T 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.
T California fuel
If your vehicle was certified to California
Emission Standards as indicated on the
underhood tune-up label, it is designed to
optimize engine and emission control sys-
tem performance with gasoline that meets
the clean burning low-sulfur California
gasoline specifications. If you live in any
other state than California, your vehicle
will operate on gasoline meeting Federal
specifications. Gasoline sold outside Cali-
fornia is permitted to have higher sulfur
levels, which may affect the performance
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
problem is fuel related before returning
your vehicle to an authorized dealer for
service. The CHECK ENGINE warning
light/Malfunction indicator lamp may also
turn on. If this occurs, return to your autho-
rized SUBARU dealer for diagnosis. If it is
determined that the condition is caused by
the type of fuel used, repairs may not be
covered by your warranty.
T 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-
Use of a fuel which is low in quality
or use of an inappropriate fuel addi-
tive may cause engine damage.