GMC 2003 Envoy - Manual (Page 301)

California Fuel
If your v^ehide cartitieci to mael Caliiomia Emissfon
Standards [see the urtderhood amissfon control label),
it Is designed to oparaie gn fuels thaï meet California
specificafions. If this fuel is not available in stales
adopting Catifomia emissions standards, your vehicle
will oporale satis-factonify on fuels meeling federal
specifications, bul emission cgntnol system perfornnaflce
may be affected. Tiio maJiunotion indicator lamp may
turn,on (see
M aiiunciion (ndicatoc L^mp on page 3-41)
and your vahfqle may fail a simog-checit test. If Ihis
occurs,. fieEitrn to your authorized GM deafer for
diagnosis. If it is determined that the condillon is caused
by the type of fuel used, repairs may not be covered
by your warrar>ty.
Additives
To provide cleaner air. all gasolines in the Unitod States
are now required lo contain additives thal will help
prevent engine and fueJ system da posits trorn fomiing,
allowing your emission conmol. system (o work
pnoporly. You should not have to add anything to your
fuel. Gasolines conlalning oxygenates, such as
ethers and ethanol, and refomiulated gasolines mfiy be
available In your area lo oonlribuie to efean arr.
General Motors recommenda thaï you use Ihese
gasolines, panicoiarly if they comply wilh lhe
specifications described earlier.
FJatic^: Your vehicle was not designed tor fuet that
contains methanol. Don'l use fuel containing
methanol. It cari corrode metal parts in your tuel
system snd also damage the plastic and rubber
parts. That damage wouldn't be covered under your
warranty.
Some gasolines that are not reformulated for low
émissions may contain an Dctane-enhaacing additive
called mel'hyfcydopeniadianyl manganese Tricarbonyf
(MMT); ash the attendant where you buy gaaoHne
whether the fuel opniains MI\AT General Motors does
not recommend ihe use of such gasolines. Fuels
canJaming MMT can reduce the Nie of spark plugs and
the perfortii^ance of (he émission control system may
be affected, The mallunclion indicalor lamp may Turn on.
|i This cccurs, return to your authorized GM dealer for
service.
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