Check Gas Cap Light
If your vehicle has this
light, it will come on if your
gas cap is not securely
fastened.
SeeMalfunction Indicator Lamp on page 3-42for more
information.
Driver Information Center (DIC)
Your vehicle may have a Driver Information Center (DIC).
All messages will appear in the DIC display located in
the instrument panel cluster, below the speedometer.
The DIC buttons are located on the center of the
instrument panel, below the center outlets.
The DIC comes on when the ignition is on. After a short
delay, the uplevel DIC will display the WELCOME
DRIVER (1 or 2) if a personalized key 1 or 2 is used,
and then the information that was last displayed before
the engine was turned off.The base level DIC displays the odometer and trip
odometers only.
The uplevel DIC displays the odometer, trip odometers,
fuel economy, trip computer, vehicle system, and
compass display information. It also displays warning
messages if a system problem is detected. In addition,
the uplevel DIC displays phone numbers that are
called using the OnStar
®system, if equipped. See
OnStar®System on page 2-43.
The outside air temperature automatically appears in
the bottom right corner of the uplevel DIC display when
viewing the trip/odometer screens, fuel screens and
some of the gages screens. If the outside air
temperature is at or below 37°F (3°C), the temperature
reading will toggle between displaying the outside
temperature and the word ICE for two minutes. If there
is a problem with the system that controls the
temperature display, the letters OC (open circuit) or SC
(short circuit) will appear on the display. If this occurs,
have the vehicle serviced by your dealer/retailer.
The uplevel DIC also allows some features to be
customized or personalized. SeeDIC Vehicle
Personalization on page 3-76for more information.
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If your vehicle has the 5.3L V8 engine (VIN Code C),
use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular unleaded
gasoline rated at 87 octane or higher, but your vehicle’s
acceleration could be slightly reduced, and you might
notice a slight audible knocking noise, commonly referred
to as spark knock. If the octane is less than 87, you might
notice a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you could damage the
engine. If you are using gasoline rated at 87 octane or
higher and you hear heavy knocking, the engine needs
service.
Gasoline Speci cations
At a minimum, gasoline should meet ASTM speci cation
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. SeeAdditives on page 5-7for
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 might be affected.
The malfunction indicator lamp could turn on and your
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-42. 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 your warranty.
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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 your vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline. Also,
your dealer/retailer has additives that will help correct and
prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available
in your area. We recommend that you use these
gasolines, if they comply with the speci cations described
earlier. However, E85 (85% ethanol) and other fuels
containing more than 10% ethanol must not be used in
vehicles that were not designed for those fuels.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under your
warranty.Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance of the
emission control system could be affected. The
malfunction indicator lamp might turn on. If this occurs,
return to your dealer/retailer for service.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not be
covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
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