Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly. In
most cases, you should not have to add anything to your
fuel. However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if your vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline. Also,
your GM dealer has additives that will help correct and
prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area. General Motors recommends that you use
these gasolines if they comply with the specifications
described earlier. However, E85 (85% ethanol) and other
fuels containing more than 10% ethanol must not be used
in vehicles that were not designed for those fuels.
Notice: Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber parts.
That damage would not be covered under your
warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors
recommends against the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs
and the performance of the emission control system may
be affected. The malfunction indicator lamp may turn
on. If this occurs, return to your authorized GM dealer for
service.
Fuel E85 (85% Ethanol)
The 8th digit of your vehicle identification number (VIN)
shows the code letter or number that identifies your
engine. You will find the VIN at the top left of the
instrument panel. See Vehicle Identification Number
(VIN) on page 5-93.
If your vehicle has the 3.5L V6 engine (VIN Code K only),
you may use either regular unleaded gasoline or ethanol
fuel containing up to 85% ethanol (E85); also see Fuel on
page 5-4. In all other engines, including the 3.5L V6 (VIN
Code N), use only regular unleaded gasoline.
Only vehicles that have the 3.5L V6 engine (VIN Code K)
may use 85% ethanol fuel (E85). General Motors
encourages the use of E85 in vehicles that are designed
to use it. The ethanol in E85 is a “renewable” fuel,
meaning it is made from renewable sources such as corn
and other crops.
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