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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.
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Black plate (9,1)Cadillac STS Owner Manual - 2011
Filling the Tank
{WARNING:
Fuel vapor burns violently and a fuel fire can
cause bad injuries. To help avoid injuries to you
and others, read and follow all the instructions on
the fuel pump island. Turn off the engine when
refueling. Do not smoke near fuel or when
refueling the vehicle. Do not use cellular phones.
Keep sparks, flames, and smoking materials away
from fuel. Do not leave the fuel pump unattended
when refueling the vehicle. This is against the law
in some places. Do not re-enter the vehicle while
pumping fuel. Keep children away from the fuel
pump; never let children pump fuel.
The tethered fuel cap
is located behind a
hinged fuel door on the
passenger side of the
vehicle.
To open the fuel door, push the rearward center edge in
and release and it will open.
To remove the fuel cap, turn it slowly counterclockwise.
The fuel cap has a spring in it; if the cap is released too
soon, it will spring back to the right.
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Black plate (12,1)Cadillac STS Owner Manual - 2011
Checking Things Under
the Hood
{WARNING:
An electric fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing, and tools away from any
underhood electric fan.
{WARNING:
Things that burn can get on hot engine parts and
start a fire. These include liquids like fuel, oil,
coolant, brake fluid, windshield washer and other
fluids, and plastic or rubber. You or others could
be burned. Be careful not to drop or spill things
that will burn onto a hot engine.
Hood Release
To open the hood:
1. Pull the hood releaselever with this symbol
on it. It is located
inside the vehicle on
the lower left side of
the instrument panel.
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Black plate (13,1)Cadillac STS Owner Manual - 2011
2. Then go to the front of the vehicle and find thesecondary hood release lever. The lever is located
under the front edge of the grille near the center.
Push the release lever up and raise the hood.
Before closing the hood, be sure all the filler caps are
on properly. Then pull the hood down and close it firmly.
Engine Compartment Overview
Your vehicle may be equipped with front compartment
underhood sight shields, which surround the vehicle's
engine cover. These sight shields will need to be
removed in order to access some of the underhood
components in your vehicle.
To remove the sight shields, turn the fasteners on each
shield to the left until they pop out. Then remove the
fasteners and lift the shields up and away from the
tower to tower brace.
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Black plate (14,1)Cadillac STS Owner Manual - 2011
3.6 L V6 Engine
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Black plate (15,1)Cadillac STS Owner Manual - 2011
After you have removed the sight shields (if equipped):A. Underhood Fuse Block. See Underhood Fuse
Block on page 6‑116.
B. Remote Negative (-) Terminal. See Jump Starting
on page 6‑38.
C. Remote Positive (+) Terminal. See Jump Starting
on page 6‑38.
D. Battery. See Battery on page 6‑38.
E. Passenger Compartment Air Filter. See Passenger
Compartment Air Filter on page 4‑50.
F. Power Steering Fluid Reservoir. See Power
Steering Fluid on page 6‑33.
G. Engine Oil Fill Cap. See “When to Add Engine Oil”
under Engine Oil on page 6‑16.
H. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 6‑16. I. Brake Master Cylinder Reservoir. See
“Brake
Fluid” under Brakes on page 6‑35.
J. Engine Coolant Surge Tank and Pressure Cap. See Cooling System on page 6‑24.
K. Engine Air Cleaner/Filter. See Engine Air Cleaner/
Filter on page 6‑21.
L. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on
page 6‑34.
If your vehicle is equipped with front compartment
underhood sight shields, before closing the hood be
sure to reinstall the sight shields. To reinstall the
shields, locate the tabs on the left and right sides and
insert them into the openings in the tower to tower
brace. Then insert the fasteners into the top of the
shield and push the fasteners back into place.
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Black plate (16,1)Cadillac STS Owner Manual - 2011
Engine Oil
To ensure proper engine performance and long life,
careful attention must be paid to engine oil. Following
these simple, but important steps will help protect your
investment:
.Always use engine oil approved to the proper
specification and of the proper viscosity grade. See
“Selecting the Right Engine Oil.”
.Check the engine oil level regularly and maintain
the proper oil level. See“Checking Engine Oil”and
“When to Add Engine Oil.”
.Change the engine oil at the appropriate time. See
Engine Oil Life System on page 6‑20.
.Always dispose of engine oil properly. See “What
to Do With Used Oil.”
Checking Engine Oil
It is a good idea to check the engine oil level at each
fuel fill. In order to get an accurate reading, the vehicle
must be on level ground. The engine oil dipstick handle
is a yellow loop. See Engine Compartment Overview
on
page 6‑13for the location of the engine oil dipstick.
Obtaining an accurate oil level reading is essential: 1. If the engine has been running recently, turn off the engine and allow several minutes for the oil to
drain back into the oil pan. Checking your oil level
too soon after engine shut off will not provide an
accurate oil level reading.
2. Pull out the dipstick and clean it with a paper towel or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
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Black plate (17,1)Cadillac STS Owner Manual - 2011
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of
the dipstick, add one liter/quart of the recommended oil
and then recheck the level. See“Selecting the Right
Engine Oil” for an explanation of what kind of oil to use.
For engine oil crankcase capacity, see Capacities and
Specifications on page 6‑128. Notice:
Do not add too much oil. Oil levels above or
below the acceptable operating range shown on the
dipstick are harmful to the engine. If you find that
you have an oil level above the operating range, i.e.
the engine has so much oil that the oil level gets
above the cross-hatched area that shows the proper
operating range, the engine could be damaged. You
should drain out the excess oil or limit your driving
of the vehicle and seek a service professional to
remove the excess amount of oil.
See Engine Compartment Overviewon page 6‑13for
the location of the engine oil fill cap.
Add enough oil to put the level somewhere in the proper
operating range. Push the dipstick all the way back in
when through.
6-17