2004 CHEVROLET EXPRESS CARGO VAN gas type

Seat Position Sensors
Vehicles with dual stage air bags are also equipped with
special sensors which enable the sensing system to
monitor the position of both the driver and passenger
front seats. The seat position sensors provide
information which is used to determine if the air bags
should deploy at a reduced level or at full depoyment.
Air Bag Systems
In any particular crash, no one can say whether an air
bag should have inated simply because of the damage
to a vehicle or because of what the repair costs were.
Ination is determined by the angle of the impact
and how quickly the vehicle slows down in front or
near-frontal impacts.
What Makes an Air Bag Inate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. The
sensing system triggers a release of gas from the
inator, which inates the air bag. The inator, air bag,
and related hardware are all part of the air bag
modules inside the steering wheel and in the instrument
panel in front of the right front passenger.
How Does an Air Bag Restrain?
In moderate to severe frontal or near-frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. Air bags supplement the
protection provided by safety belts. Air bags distribute
the force of the impact more evenly over the occupant’s
upper body, stopping the occupant more gradually.
But air bags would not help you in many types of
collisions, including rollovers, rear impacts and many
side impacts, primarily because an occupant’s motion is
not toward those air bags. Air bags should never be
regarded as anything more than a supplement to safety
belts, and then only in moderate to severe frontal or
near-frontal collisions.
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California Fuel
If your vehicle is certied to meet California Emission
Standards (see the underhood emission control label), it
is designed to operate on fuels that meet California
specications. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (seeMalfunction Indicator Lamp on page 3-34)
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. However, some gasolines contain only the
minimum amount of additive required to meet U.S.
Environmental Protection Agency regulations. General
Motors recommends that you buy gasolines that
are advertised to help keep fuel injectors and intake
valves clean. If your vehicle experiences problems due
to dirty injectors or valves, try a different brand of
gasoline.
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 specications described earlier.
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Be careful not to spill fuel. Clean fuel from painted
surfaces as soon as possible. SeeCleaning the Outside
of Your Vehicle on page 5-95. When lling the tank
do not overll by squeezing in much more fuel after the
pump shuts off.
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. SeeMalfunction Indicator Lamp on
page 3-34.
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. SeeMalfunction Indicator Lamp on
page 3-34.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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Bulb Replacement
For any bulb changing procedure not listed in this
section, contact your dealer.
For the type of bulbs, seeReplacement Bulbs on
page 5-56.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the bulb.
You or others could be injured. Be sure to read
and follow the instructions on the bulb
package.
Headlamps
1. Remove the two bolts from the headlamp assembly.
2. Remove the two pins on the top of the headlamp
assembly. To remove the pins, turn the outer pin
clockwise and pull it straight up. To remove
the inner pin, turn it counterclockwise and pull it
straight up.
3. Lift the inboard side of the headlamp to release the
inboard tab from the radiator support.
4. Lift the outboard side of the headlamp to release
the outboard tab from the radiator support.
5. Lower the headlamp to allow the vertical adjustor to
clear tie bar.
6. Turn the headlamp forward and upward to remove
it from the grille.
7. Turn the bulb connector counterclockwise and pull it
out of the housing.
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