gas type CHEVROLET IMPALA 2008 9.G Owners Manual

Page 64 of 400

What Makes an Airbag Inate?
In a deployment event, the sensing system sends an
electrical signal triggering a release of gas from the
inator. Gas from the inator lls the airbag causing the
bag to break out of the cover and deploy. The inator,
the airbag, and related hardware are all part of the airbag
module.
Frontal airbag modules are located inside the steering
wheel and instrument panel. For vehicles with
roof-rail airbags, there are airbag modules in the ceiling
of the vehicle, near the side windows that have
occupant seating positions.
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle.
Airbags supplement the protection provided by safety
belts. Frontal airbags distribute the force of the
impact more evenly over the occupant’s upper body,
stopping the occupant more gradually. Roof-rail airbags
distribute the force of the impact more evenly over
the occupant’s upper body.But airbags would not help in many types of collisions,
primarily because the occupant’s motion is not
toward those airbags. SeeWhen Should an Airbag
Inflate? on page 1-59for more information.
Airbags should never be regarded as anything more
than a supplement to safety belts.
What Will You See After an
Airbag Inates?
After the frontal airbags inate, they quickly deate,
so quickly that some people may not even realize
an airbag inated. Roof-rail airbags may still be at least
partially inated for some time after they deploy.
Some components of the airbag module may be hot for
several minutes. For location of the airbag modules,
seeWhat Makes an Airbag Inflate? on page 1-60.
The parts of the airbag that come into contact with you
may be warm, but not too hot to touch. There may be
some smoke and dust coming from the vents in
the deated airbags. Airbag ination does not prevent
the driver from seeing out of the windshield or being
able to steer the vehicle, nor does it prevent people
from leaving the vehicle.
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Page 252 of 400

Gasoline Octane
For all vehicles except those with the 5.3L V8 engine
(VIN Code C), use regular unleaded gasoline with
a posted octane rating of 87 or higher. If the octane
rating is less than 87, you might notice an audible
knocking noise when you drive, commonly referred to
as spark knock. If this occurs, use a gasoline rated
at 87 octane or higher as soon as possible. If you are
using gasoline rated at 87 octane or higher and you hear
heavy knocking, the engine needs service.
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 Specications
At a minimum, gasoline should meet ASTM
Specication 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 certied to meet California Emissions
Standards, it is designed to operate on fuels that
meet California specications. 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 specications, 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 3-39. 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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Page 257 of 400

{CAUTION:
Fuel can spray out on you if you open the fuel
cap too quickly. If you spill fuel and then
something ignites it, you could be badly burned.
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 overll 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 5-93.
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 3-39.The TIGHTEN GAS CAP message will be displayed on
the Driver Information Center (DIC) if the fuel cap is
not properly installed. SeeDIC Warnings and Messages
on page 3-52for 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/retailer 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 3-39.
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Page 293 of 400

To disconnect the jumper cables from both vehicles,
do the following:
1. Disconnect the black negative (−) cable from the
vehicle that had the dead battery.
2. Disconnect the black negative (−) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5. Return the fuse block cover to its original position.
Headlamp Aiming
Headlamp aim has been preset at the factory and
should need no further adjustment.
However, if your vehicle is damaged in a crash, the
headlamp aim may be affected. Aim adjustment to the
low-beam headlamps may be necessary if oncoming
drivers ash their high-beam headlamps at you
(for vertical aim).
If the headlamps need to be re-aimed, it is
recommended that you take the vehicle to your
dealer/retailer for service.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-52.
For any bulb changing procedure not listed in this
section, contact your dealer/retailer.
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.
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