CHEVROLET TAHOE 2003 2.G Owners Manual
Manufacturer: CHEVROLET, Model Year: 2003, Model line: TAHOE, Model: CHEVROLET TAHOE 2003 2.GPages: 552, PDF Size: 3.44 MB
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Gasoline Octane
Use regular unleaded gasoline with a posted octane of 87
or higher. If the octane is less than 87, you may get 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 might damage your engine.
A little pinging noise when you accelerate or drive uphill is
considered normal. This does not indicate a problem
exists or that a higher-octane fuel is necessary. If you are
using 87 octane or higher-octane fuel and hear heavy
knocking, your engine needs service.
Gasoline Speci®cations
It is recommended that gasoline meet speci®cations
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers Association for better
vehicle performance and engine protection. Gasoline
meeting these speci®cations could provide improved
driveability and emission control system performance
compared to other gasoline.
In Canada, look for the
ªAuto Makers' Choiceº
label on the pump.
Canada Only
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California Fuel
If your vehicle is certi®ed to meet California Emission
Standards (see the underhood emission control label), it
is designed to operate on fuels that meet California
speci®cations. 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 (see
Malfunction Indicator Lamp on page 3-47) and
your vehicle may fail a smog-check test. 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.
You should not have to add anything to your fuel.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the speci®cations described earlier.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
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Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer for
service.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identi®cation number (VIN)
shows the code letter or number that identi®es your
engine. You will ®nd the VIN at the top left of the
instrument panel. See
Vehicle Identi®cation Number
(VIN) on page 5-107.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also see
Fuel on page 5-4. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.Only vehicles that have the 5.3L V8 engine (VIN Code Z)
may use 85% ethanol fuel (E-85).
Many service stations will not have an 85% ethanol fuel
(E-85) pump available. The U. S. Department of
Energy has an alternative fuels website
(http://afdcmap.nrel.gov/nrel/) that can help you ®nd
E-85 fuel. Those stations that do have E-85 should have
a label indicating ethanol content. Do not use the fuel
if the ethanol content is
greaterthan 85%. Your vehicle
may not operate properly if the ethanol content is
greater than 85%.
At a minimum, E-85 should meet ASTM Speci®cation
D 5798.
To insure quick starts in the wintertime, the E-85 fuel
must be formulated properly for your climate according
to ASTM speci®cation D 5798. If you have trouble
starting on E-85, it may be because your E-85 fuel is
not properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to your fuel
tank may improve starting. Your vehicle is designed to
accommodate a mixture of gasoline and E-85 fuel.
For good starting and heater efficiency below 32ÉF
(0ÉC), the fuel mix in the fuel tank should contain no
more than 70% ethanol.
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E-85 has less energy per gallon than gasoline, so you'll
need to re®ll your fuel tank more often when using
E-85 than when you're using gasoline. Regular unleaded
gasoline is recommended when pulling a trailer. For
payload capacity with ethanol fuel, see
Loading
Your Vehicle on page 4-62.
Notice:Some additives are not compatible with
E-85 fuel and may harm your fuel system. Damage
caused by additives wouldn't be covered by
your new vehicle warranty. Don't use additives with
E-85 fuel.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may 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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Filling Your Tank
{CAUTION:
Fuel vapor is highly ¯ammable. It burns
violently, and that can cause very bad injuries.
Do not smoke if you are near fuel or refueling
your vehicle. Keep sparks, ¯ames and smoking
materials away from fuel.
The fuel cap is located behind a hinged door on the
driver's side of the vehicle.
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While refueling, hang the fuel cap by the tether using
the hook located on the inside of the ®ller door.To remove the fuel cap, turn it slowly to the left
(counterclockwise).
{CAUTION:
If you get fuel on yourself 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 ªhissº
noise to stop. Then unscrew the cap all the way.
Be careful not to spill fuel. Clean fuel from painted
surfaces as soon as possible. See
Cleaning the Outside
of Your Vehicle on page 5-102.
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When you put the fuel cap back on, turn it to the right
(clockwise) until you hear a clicking sound. Make sure
you fully install the cap. 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. See
Malfunction Indicator Lamp on
page 3-47.
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 ªMalfunction Indicator Lampº in the Index.
Filling a Portable Fuel Container
{CAUTION:
Never ®ll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
·Dispense gasoline only into approved
containers.
·Do not ®ll a container while it is inside a
vehicle, in a vehicle's trunk, pickup bed or
on any surface other than the ground.
·Bring the ®ll nozzle in contact with the
inside of the ®ll opening before operating
the nozzle. Contact should be maintained
until the ®lling is complete.
·Do not smoke while pumping gasoline.
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Checking Things Under
the Hood
{CAUTION:
Things that burn can get on hot engine parts
and start a ®re. These include liquids like fuel,
oil, coolant, brake ¯uid, windshield washer and
other ¯uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
Hood Release
To open the hood do the following:
1. Pull the handle inside
the vehicle located
under and to the left of
the steering wheel.
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2. Then go to the front of the vehicle and pull up on
the secondary hood release located near the
center of the grill.
3. Lift the hood.
Before closing the hood, be sure all ®ller caps are
on properly. Pull down the hood and close it ®rmly.
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Engine Compartment Overview
When you open the hood on the VORTECŸ 5300 V8 engine (VORTECŸ 4800 and 6000 V8 engines similar), you'll
see the following:
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