Gasoline Specifications; California Fuel; Additives - Cadillac 2010 DTS Owner's Manual

If this occurs, use a gasoline rated at 87 octane or
higher as soon as possible. Otherwise, you could
damage the engine. If heavy knocking is heard when
using gasoline rated at 87 octane or higher, 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 6-6 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.
6-6
See Malfunction Indicator Lamp on page 4-57. 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, nothing should have to be added 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.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every
engine oil change, can help clean deposits from fuel
injectors and intake valves. GM Fuel System Treatment
PLUS is the only gasoline additive recommended by
General Motors.
Also, your dealer/retailer has additives that will help
correct and prevent most deposit-related problems.