2007 CADILLAC STS engine

Accessories and Modications
When you add non-GM accessories to your vehicle
they can affect your vehicle’s performance and
safety, including such things as, airbags, braking,
stability, ride and handling, emissions systems,
aerodynamics, durability, and electronic systems
like anti-lock brakes, traction control and stability
control. Some of these accessories may even
cause malfunction or damage not covered by
warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle.
Your GM dealer can accessorize your vehicle
using genuine GM Accessories. When you go to
your GM dealer and ask for GM Accessories,
you will know that GM-trained and supported
service technicians will perform the work using
genuine GM Accessories.
California Proposition 65 Warning
Most motor vehicles, including this one, contain
and/or emit chemicals known to the State of
California to cause cancer and birth defects or other
reproductive harm. Engine exhaust, many parts and
systems (including some inside the vehicle), many
uids, and some component wear by-products
contain and/or emit these chemicals.
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Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your
vehicle can affect the airow around it. This may
cause wind noise and affect windshield washer
performance. Check with your dealer before
adding equipment to the outside of your vehicle.
Fuel
Use of the recommended fuel is an important part
of the proper maintenance of your vehicle. To
help keep your engine clean and maintain optimum
vehicle performance, GM recommends the use
of gasoline advertised as TOP TIER Detergent
Gasoline.
The 8th digit of your Vehicle Identication
Number (VIN) shows the code letter or number
that identies your engine. You will nd the VIN at
the top left of the instrument panel. SeeVehicle
Identication Number (VIN) on page 485.
Gasoline Octane
If your vehicle has the 3.6L V6 engine
(VIN Code 7), use regular unleaded gasoline with
a posted octane rating of 87 or higher. For
best performance or trailer towing, you may
choose to use middle grade 89 octane unleaded
gasoline. If the octane rating is less than 87,
you may notice an audible knocking noise when
you drive, commonly referred to as spark knock. If
this occurs, use a gasoline rated at 87 octane
or higher as soon as possible. If you are using
gasoline rated at 87 octane or higher and you hear
heavy knocking, your engine needs service.
If your vehicle has the 4.6L V8 engine
(VIN Code A), use premium unleaded gasoline with
a posted octane rating of 91 or higher. You may
also use regular unleaded gasoline rated at
87 octane or higher, but your vehicle’s acceleration
may be slightly reduced, and you may notice a
slight audible knocking noise, commonly referred to
as spark knock.
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If the octane is less than 87, you may notice a
heavy knocking noise when you drive. If this occurs,
use a gasoline rated at 87 octane or higher as soon
as possible. Otherwise, you might damage your
engine. If you are using gasoline rated at 87 octane
or higher and you hear heavy knocking, your engine
needs service.
If your vehicle has the 4.4L V8 engine
(VIN Code D), 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 may also
hear audible spark knock during acceleration. Rell
your tank with premium fuel as soon as possible to
avoid damaging your engine. If you are using
gasoline rated at 91 octane or higher and you hear
heavy knocking, your engine needs service.Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 367for additional information.
California Fuel
If your vehicle is certied to meet California
Emissions Standards, it is designed to operate on
fuels that meet California specications. 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 specications, but emission
control system performance may be affected.
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The malfunction indicator lamp may turn on and
your vehicle may fail a smog-check test. See
Malfunction Indicator Lamp on page 252. If this
occurs, return to your authorized GM dealer for
diagnosis. If it is determined that the condition is
caused by the type of fuel used, repairs may not be
covered by your warranty.
Additives
To provide cleaner air, all gasolines in the United
States are now required to contain additives
that will help prevent engine and fuel system
deposits from forming, allowing your emission
control system to work properly. In most cases,
you should not have to add anything to your 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 that is
advertised as TOP TIER Detergent Gasoline. Also,
your dealer has additives that will help correct
and prevent most deposit-related problems.Gasolines containing oxygenates, such as ethers
and ethanol, and reformulated gasolines may
be available in your area. General Motors
recommends that you use these gasolines if they
comply with the specications 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 may contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant where you
buy gasoline whether the fuel contains MMT.
General Motors recommends against the use of
such gasolines. Fuels containing MMT can reduce
the life of spark plugs and the performance of
the emission control system may be affected. The
malfunction indicator lamp may turn on. If this
occurs, return to your dealer for service.
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Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be
hard to nd. Never use leaded gasoline or any other
fuel not recommended in the previous text on fuel.
Costly repairs caused by use of improper fuel would
not be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business
in the country where you will be driving.
Filling the Tank
{CAUTION:
Fuel vapor burns violently and a fuel re
can cause bad injuries. To help avoid
injuries to you and others, read and follow
all the instructions on the pump island.
Turn off your engine when you are
refueling. Do not smoke if you are near
fuel or refueling your vehicle. Do not use
cellular phones. Keep sparks, ames, and
smoking materials away from fuel. Do not
leave the fuel pump unattended when
refueling your vehicle. This is against the
law in some places. Do not re-enter
vehicle while pumping fuel. Keep children
away from the fuel pump; never let
children pump fuel.
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Checking Things Under
the Hood
{CAUTION:
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.
{CAUTION:
Things that burn can get on hot engine
parts and start a re. These include
liquids like fuel, oil, coolant, brake uid,
windshield washer and other uids, 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, do the following:
1. Pull the hood
release lever with
this symbol on
it. It is located inside
the vehicle on the
lower left side of the
instrument panel.
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2. Then go to the front of the vehicle and nd
the secondary hood release lever. The lever
is located under the front edge of the
grille near the center. Move the release lever
to the side and raise the hood.
Before closing the hood, be sure all the ller caps
are on properly. Then pull the hood down and
close it rmly.
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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3.6L V6 Engine
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