Saturn 2009 ASTRA - Manual (Page 180)

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.
Gasoline Octane
Use regular unleaded gasoline with a
posted octane rating of 87 or higher.
If the octane rating is less than 87,
you might notice an audible knocking
noise when you drive, commonly
referred to as spark knock. If this
occurs, use a gasoline rated at
87 octane or higher as soon as
possible. If you are using gasoline
rated at 87 octane or higher and you
hear heavy knocking, the engine
needs service.
Gasoline Specifications
At a minimum, gasoline should
meet ASTM specification D 4814
in the United States or
CAN/CGSB-3.5 or 3.511 in Canada.
Some gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. See Additives on
page 8-34 for additional information.
California Fuel
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
might fail a smog-check test. See
Malfunction Indicator Lamp on
page 4-18. If this occurs, return to
your authorized dealer/retailer for
diagnosis. If it is determined that the
condition is caused by the type of
fuel used, repairs might not be
covered by the vehicle warranty.
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, you
should not have to add anything 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, or
if the vehicle experiences problems
due to dirty injectors or valves,
look for gasoline that is advertised
as TOP TIER Detergent Gasoline.
8-34 Driving and Operating