Cadillac 2009 CTS, Owner'S Manual

Page: 313 / 494

If the vehicle has the 6.2L supercharged V8 engine
(VIN Code P), use premium unleaded gasoline with
a posted octane rating of 91 or higher. For best
performance, use premium unleaded gasoline with a
posted octane rating of 93. In an emergency, you can use
regular unleaded gasoline with an octane rating of 87 or
higher. If 87 octane fuel is used, do not perform any
aggressive driving maneuvers such as wide open throttle
applications. You might also hear audible spark knock
during acceleration. Refill the tank with premium fuel as
soon as possible to avoid damaging the engine. If you are
using gasoline rated at 91 octane or higher and you hear
heavy knocking, the engine needs service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM specification
D 4814 in the United States or CAN/CGSB-3.5 or
3.511 in Canada. Some gasolines contain an
octane-enhancing additive called methylcyclopentadienyl
manganese tricarbonyl (MMT). We recommend
against the use of gasolines containing MMT. See
Additives on page 5-7 for additional information.
California Fuel
If the 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, the
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 the vehicle might fail a smog-check
test. See Malfunction Indicator Lamp on page 3-42.
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 the vehicle 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 the vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline.
5-7