gas type GMC ACADIA 2007 Owner's Manual

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 seat-mounted side impact airbags, there
are airbag modules in the side of the front
seatbacks closest to the door. 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.
Seat-mounted side impact and roof-rail airbags
distribute the force of the impact more evenly over
the occupant’s upper body.
Rollover capable roof-rail airbags are designed to
help contain the head and chest of occupants
in the outboard seating positions in the rst,
second, and third rows. The rollover capable
roof-rail airbags are designed to help reduce the
risk of full or partial ejection in rollover events,
although no system can prevent all such ejections.
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 81for more information.
Airbags should never be regarded as anything
more than a supplement to safety belts.
83

Gasoline Octane
Use regular unleaded gasoline with a posted
octane rating of 87 or higher. For best performance
or trailer towing, you could choose to use middle
grade 89 octane unleaded gasoline. 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.
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 389for 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 226. 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.
388

{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 482.
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 226.If your vehicle has a Driver Information Center
(DIC), the TIGHTEN GAS CAP message will be
displayed if the fuel cap is not properly installed.
{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 226.
392

Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 433.
For any bulb changing procedure not listed in this
section, contact your dealer/retailer.
High Intensity Discharge (HID)
Lighting
{CAUTION:
The high beam and low beam high
intensity discharge lighting system
operates at a very high voltage. If you try
to service any of the system components,
you could be seriously injured. Have your
dealer/retailer or a qualied technician
service them.Your vehicle may have HID headlamps. After your
vehicle’s HID headlamp bulb has been replaced,
you may notice that the beam is a slightly different
shade than it was originally. This is normal.
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.
432