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What Makes an Airbag Inflate?
In a deployment event, the sensing system sends anelectrical signal triggering a release of gas fromthe inflator. Gas from the inflator fills the airbag causingthe bag to break out of the cover and deploy. Theinflator, the airbag, and related hardware are all part ofthe airbag module.
Frontal airbag modules are located inside the steeringwheel and instrument panel. For vehicles withseat-mounted side impact airbags, there are airbagmodules in the side of the front seatbacks closest to thedoor. For vehicles with roof-rail airbags, there areairbag modules in the ceiling of the vehicle, near theside 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 orthe instrument panel. In moderate to severe sidecollisions, even belted occupants can contact the insideof the vehicle.
Airbags supplement the protection provided by safetybelts. Frontal airbags distribute the force of theimpact more evenly over the occupant’s upper body,stopping the occupant more gradually. Seat-mountedside impact and roof-rail airbags distribute the forceof the impact more evenly over the occupant’supper body.
But airbags would not help in many types of collisions,primarily because the occupant’s motion is nottoward those airbags. SeeWhen Should an AirbagInflate? on page 2-63for more information.
Airbags should never be regarded as anything morethan a supplement to safety belts.
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Page 326 of 480

If this occurs, use a gasoline rated at 87 octane orhigher as soon as possible. Otherwise, you coulddamage the engine. If heavy knocking is heard whenusing gasoline rated at 87 octane or higher, the engineneeds service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM specificationD 4814 in the United States or CAN/CGSB-3.5 or3.511 in Canada. Some gasolines contain anoctane-enhancing additive called methylcyclopentadienylmanganese tricarbonyl (MMT). We recommendagainst the use of gasolines containing MMT. SeeAdditives on page 6-6for additional information.
California Fuel
If the vehicle is certified to meet California EmissionsStandards, it is designed to operate on fuels thatmeet California specifications. See the underhoodemission control label. If this fuel is not availablein states adopting California emissions standards, thevehicle will operate satisfactorily on fuels meeting federalspecifications, but emission control system performancemight be affected. The malfunction indicator lampcould turn on and the vehicle might fail asmog-check test.
SeeMalfunction Indicator Lamp on page 4-57. If thisoccurs, return to your authorized dealer/retailer fordiagnosis. If it is determined that the condition is causedby the type of fuel used, repairs might not be coveredby the vehicle warranty.
Additives
To provide cleaner air, all gasolines in the United Statesare now required to contain additives that help preventengine and fuel system deposits from forming, allowingthe emission control system to work properly. In mostcases, nothing should have to be added to the fuel.However, some gasolines contain only the minimumamount of additive required to meet U.S. EnvironmentalProtection Agency regulations. To help keep fuel injectorsand intake valves clean, or if the vehicle experiencesproblems due to dirty injectors or valves, look for gasolinethat is advertised as TOP TIER Detergent Gasoline.
For customers who do not use TOP TIER DetergentGasoline regularly, one bottle of GM Fuel SystemTreatment PLUS, added to the fuel tank at everyengine oil change, can help clean deposits from fuelinjectors and intake valves. GM Fuel System TreatmentPLUS is the only gasoline additive recommended byGeneral Motors.
Also, your dealer/retailer has additives that will helpcorrect and prevent most deposit-related problems.
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To remove the fuel cap, turn it slowly counterclockwise.The fuel cap has a spring in it; if the cap is releasedtoo soon, it will spring back to the right.
While refueling, hang the tethered fuel cap from thehook on the fuel door.
{WARNING:
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 the 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 overfill thetank and wait a few seconds after you have finishedpumping before removing the nozzle. Clean fuelfrom painted surfaces as soon as possible. SeeWashing Your Vehicle on page 6-95.
When replacing the fuel cap, turn it clockwise until itclicks. Make sure the cap is fully installed. Thediagnostic system can determine if the fuel cap has
been left off or improperly installed. This would allowfuel to evaporate into the atmosphere. SeeMalfunctionIndicator Lamp on page 4-57.
The TIGHTEN GAS CAP message displays on theDriver Information Center (DIC) if the fuel cap isnot properly installed. SeeDIC Warnings and Messageson page 4-67for more information.
{WARNING:
If a fire starts while you are refueling, do not
remove the nozzle. Shut off the flow 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 getthe right type. Your dealer/retailer can get onefor you. If you get the wrong type, it may not fitproperly. This may cause the malfunction indicatorlamp to light and may damage the fuel tank andemissions system. SeeMalfunction Indicator Lampon page 4-57.
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