GMC 2003 Sierra - Manual (Page 381)

California Fuel
If your veliide Is certified to meel Califomia Emission'
Standards {gee the underhood emissiori controt tabal), it
ÉS ctesigned to operata on fuele that meet California
specificationg. II this fuel
js
not avgiiaPle in states
adopting California emiggions standards, your vehicle
A III operate satigfaotculy on tuels meeting federal
specifications, but emission control system perfonrignce
may be affected, The mafrunttlort Indicator lamp may
turn on (see
MaffufíCtiún indicator Lamp on page 3-44)
and your vehicle may fail a smog-check lest. If this
occurs, return to your authonzed GM dealer lor
diagnosis. If il is dntermined that the condition is caused
by the type of fuel used, repairs may not be covered
by your
lArarranly.
Additives
To provide cleaner air, all gasolines in the United Siaies
are novii required to contain additives that will help
prevent engine and fuel system deposits from fonriing,
allowing your emission control system to work
properly. You should not have to add anything to your
fuel. Gasolines containing oxyggnates, such as
ethers and ethanol, and reformulated gasotfnes may be
avaiJable in your area to conlnpute to clean air^
Goneral Motors recommands that you use these
gasoilnes, particularly if they compfy with fha
gpeoif¡cations described earlier.
Notfce: Your vehicle was not designed tor fuel lhal
contains methanol. Don't use fuel containing
methanoL it can corrode meiel parts in your fuel
system and also damage the plastic and rubber
parts. That damage wouldnT be covered under your
warranty.
Some gasolines that are not reformulated for low
emfggions may contam an octane-eohandr>g additive
called n^ethylcyciopentadlenyl manga ne&e
tricartjonyf iMNiTjl ssk Ihe attendant where you buy
gasoline whelhar the fuel contains MMT. General Motors
does not recommend the use of ggch gasolines.
Fuels containing
M M T can reduce the Nfe of spark plugs
and tile pertormance of Ihe emisgion coni rol system
may be affected. The malfunction indlcalor lamp
may turn on. If this occurs, return to your authorized GM
dealer for service.
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