
Black plate (7,1)Cadillac STS Owner Manual - 2011
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. SeeAdditives
on page 6‑7for 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 4‑62. If this
occurs, return to your authorized dealer 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. It is available at your dealer.
6-7

Black plate (10,1)Cadillac STS Owner Manual - 2011
While refueling, hang the tethered fuel cap from the
hook on the fuel door.
{WARNING:
Fuel can spray out on you if you open the fuel cap
too quickly. If you spill fuel and then something
ignites it, you could be badly burned. This spray
can happen if the tank is nearly full, and is more
likely in hot weather. Open the fuel cap slowly and
wait for any hiss noise to stop. Then unscrew the
cap all the way.
Be careful not to spill fuel. Do not top off or overfill the
tank, and wait a few seconds after you have finished
pumping before removing the nozzle. Clean fuel from
painted surfaces as soon as possible. See Washing
Your Vehicle on page 6‑109. When replacing the fuel cap, turn it clockwise until it
clicks. Make sure the cap is fully installed. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. This would allow
fuel to evaporate into the atmosphere. See
Malfunction
Indicator Lamp on page 4‑62.
The CHECK GAS CAP message will appear on the
Driver Information Center (DIC) display if the fuel cap is
not reinstalled properly. See DIC Warnings and
Messages
on page 4‑76for more information.
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Black plate (6,1)Cadillac STS Owner Manual - 2011
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . 6-11
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-68
Fuel Economy Driving for Better . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
Fuses Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . 6-115
Rear Underseat Fuse Block . . . . . . . . . . . . . . . . . . . . .6-120
Underhood Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Windshield Wiper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
G
Garage Door Opener . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-49
GasolineOctane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 Gauges
Engine Coolant Temperature . . . . . . . . . . . . . . . . . . . . . 4-61
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-68
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-53
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-53
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-56
GM Mobility Reimbursement Program . . . . . . . . . . . . . . .8-7
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
Hazard Warning Flashers . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
Head Restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Head-Up Display (HUD) . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-38
Headlamp Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-27 Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-46
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . . 4-32
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
High Intensity Discharge (HID) Lighting . . . . . . . . . . . 6-47
High/Low Beam Changer . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
On Reminder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-31
Range Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Wiper Activated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-31
Heated Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
i - 6