Gasoline Speci cations
At a minimum, gasoline should meet ASTM
speci cation D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 344for additional information.
California Fuel
If your vehicle is certi ed to meet California
Emissions Standards, it is designed to operate
on fuels that meet California speci cations.
See the underhood emission control label.
If this fuel is not available in states adopting
California emissions standards, your vehicle will
operate satisfactorily on fuels meeting federal
speci cations, but emission control system
performance may be affected. The malfunction
indicator lamp may turn on and your vehicle may
fail a smog-check test. SeeMalfunction Indicator
Lamp on page 190. 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
To provide cleaner air, all gasolines in the
United States are now required to contain additives
that will help prevent engine and fuel system
deposits from forming, allowing your emission
control system to work properly. In most cases,
you should not have to add anything to your
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 your vehicle experiences problems due
to dirty injectors or valves, look for gasoline that
is advertised as TOP TIER Detergent Gasoline.
Also, your dealer has additives that will help
correct and prevent most deposit-related problems.
Gasolines containing oxygenates, such as
ethers and ethanol, and reformulated gasolines
may be available in your area. General Motors
recommends that you use these gasolines if they
comply with the speci cations described earlier.
344
{CAUTION:
If you spill fuel and then something
ignites it, you could be badly burned.
Fuel can spray out on you if you open
the fuel cap too quickly. This spray can
happen if your tank is nearly full, and is
more likely in hot weather. Open the fuel
cap slowly and wait for any hiss noise to
stop. Then unscrew the cap all the way.
Be careful not to spill fuel. Do not top off or over ll
the tank and wait a few seconds after you have
nished pumping before removing the nozzle.
Clean fuel from painted surfaces as soon as
possible. SeeWashing Your Vehicle on page 442.
When replacing the fuel cap, turn it clockwise until
it clicks. Make sure the cap is fully installed. The
diagnostic system can determine if the fuel cap
has been left off or improperly installed. This would
allow fuel to evaporate into the atmosphere.
SeeMalfunction Indicator Lamp on page 190.Your vehicle may also have a check gas cap
warning light, which will be displayed on the
instrument panel cluster if the fuel cap is not
properly installed. SeeCheck Gas Cap Light
on page 199for more information.
If your vehicle has a Driver Information Center
(DIC), the CHECK GAS CAP message will
be displayed if the fuel cap is not properly
installed. SeeDIC Warnings and Messages
on page 208for more information.
{CAUTION:
If a re starts while you are refueling,
do not remove the nozzle. Shut off the
ow of fuel by shutting off the pump or
by notifying the station attendant. Leave
the area immediately.
Notice:If you need a new fuel cap, be sure to
get the right type. Your dealer can get one for
you. If you get the wrong type, it may not t
properly. This may cause your malfunction
indicator lamp to light and may damage
your fuel tank and emissions system. See
Malfunction Indicator Lamp on page 190.
347
