California Fuel; Additives - Chevrolet 2008 Tahoe Owner's Manual

California Fuel

If your vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specifications. 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 specifications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and your
vehicle might fail a smog-check test. See Malfunction
Indicator Lamp on page 3-48. 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.

Additives

To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, you should not have to add anything to the 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
5-6
that is advertised as TOP TIER Detergent Gasoline. Also,
your dealer/retailer has additives that will help correct and
prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available
in your area. We recommend 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 the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under your
warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance of the
emission control system could be affected. The
malfunction indicator lamp might turn on. If this occurs,
return to your dealer/retailer for service.