Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.

Gasoline Octane

Usepremium unleaded gasoline with a posted octane of
91or higher for best performance. You may also use
middlegrade or regular unleaded gasoline rated at 87
octaneor higher, but your vehicle’s acceleration may be
slightlyreduced. If the octane is less than 87, you may
geta heavy knocking noise when you drive. If this occurs,
usea gasoline rated at 87 octane or higher as soon as
possible.Otherwise, you might damage your engine.

Gasoline Specifications

Itis recommended that gasoline meet specifications
whichwere developed by automobile manufacturers
aroundthe world and contained in the World-Wide Fuel
Charterwhich is available from the Alliance of Automobile
Manufacturersat www.autoalliance.org/fuel_charter.htm.
Gasolinemeeting these specifications could provide
improveddriveability and emission control system
performancecompared to other gasoline.

California Fuel

If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label), it
is designed to operate on fuels that meet California
specifications. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on and your vehicle may fail a smog-check test. See
Malfunction Indicator Lamp on page3-41. If this
occurs, return to your authorized GM 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.

Additives

Toprovide cleaner air, all gasolines in the United States
arenow required to contain additives that will help
preventengine and fuel system deposits from forming,
allowingyour emission control system to work properly. In
mostcases, you should not have to add anything to your
fuel.However, some gasolines contain only the minimum
amountof additive required to meet U.S. Environmental
ProtectionAgency regulations.
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