octane CADILLAC STS 2006 1.G Owners Manual

If the Light Is On Steady
You also may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling the Tank on page 5-8. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run as efficiently as designed.You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misring, hesitation
on acceleration, or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to x any
mechanical or electrical problems that may have
developed.
3-69

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-18
Engine Oil Life System..................................5-22
Engine Air Cleaner/Filter................................5-24
Automatic Transmission Fluid.........................5-26
Engine Coolant.............................................5-26
Coolant Surge Tank Pressure Cap..................5-30
Engine Overheating.......................................5-30
Overheated Engine Protection
Operating Mode........................................5-31Cooling System............................................5-32
Power Steering Fluid.....................................5-39
Windshield Washer Fluid................................5-40
Brakes........................................................5-41
Battery........................................................5-44
Jump Starting...............................................5-45
All-Wheel Drive..............................................5-50
Rear Axle.......................................................5-51
Front Axle......................................................5-52
Bulb Replacement..........................................5-53
High Intensity Discharge (HID) Lighting............5-53
Halogen Bulbs..............................................5-53
Back-Up Lamps............................................5-54
Replacement Bulbs.......................................5-54
Windshield Replacement.................................5-55
Windshield Wiper Blade Replacement..............5-55
Tires..............................................................5-56
Tire Sidewall Labeling...................................5-58
Tire Terminology and Denitions.....................5-60
Run-Flat Tires (STS-V)..................................5-63
Ination - Tire Pressure.................................5-64
Tire Pressure Monitor System.........................5-66
Tire Inspection and Rotation...........................5-70
When It Is Time for New Tires.......................5-71
Section 5 Service and Appearance Care
5-1

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
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 5-103.
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. 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.
5-5

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 5-6
for 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.
The malfunction indicator lamp may turn on and your
vehicle may fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-67. 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.
5-6

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 GM 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 your fuel
system and also damage the 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 authorized GM dealer
for service.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may 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.
5-7

This schedule is for vehicles that:
carry passengers and cargo within recommended
limits. You will nd these limits on the Tire and
Loading Information label. SeeLoading Your
Vehicle on page 4-32.
are driven on reasonable road surfaces within legal
driving limits.
use the recommended fuel. SeeGasoline Octane
on page 5-5.
The services inScheduled Maintenance on page 6-4
should be performed when indicated. SeeAdditional
Required Services on page 6-6andMaintenance
Footnotes on page 6-7for further information.
{CAUTION:
Performing maintenance work on a vehicle
can be dangerous. In trying to do some jobs,
you can be seriously injured. Do your own
maintenance work only if you have the
required know-how and the proper tools and
equipment for the job. If you have any doubt,
see your GM Goodwrench
®dealer to have a
qualied technician do the work.Some maintenance services can be complex. So,
unless you are technically qualied and have the
necessary equipment, you should have your
GM Goodwrench
®dealer do these jobs.
When you go to your GM Goodwrench
®dealer for your
service needs, you will know that GM-trained and
supported service technicians will perform the work
using genuine GM parts.
If you want to purchase service information, seeService
Publications Ordering Information on page 7-14.
Owner Checks and Services on page 6-8tells you what
should be checked, when to check it, and what you
can easily do to help keep your vehicle in good
condition.
The proper replacement parts, uids, and lubricants to
use are listed inRecommended Fluids and Lubricants
on page 6-12andNormal Maintenance Replacement
Parts on page 6-14. When your vehicle is serviced,
make sure these are used. All parts should be replaced
and all necessary repairs done before you or anyone
else drives the vehicle. We recommend the use of
genuine GM parts.
6-3

Engine
Air Cleaner/Filter.........................................5-24
Battery.......................................................5-44
Check and Service Engine Soon Light............3-67
Coolant......................................................5-26
Coolant Heater............................................2-27
Coolant Temperature Gage...........................3-67
Coolant Temperature Warning Light................3-66
Drive Belt Routing.......................................6-15
Engine Compartment Overview......................5-12
Exhaust.....................................................2-39
Oil .............................................................5-18
Oil Life System...........................................5-22
Overheated Protection Operating Mode...........5-31
Overheating................................................5-30
Starting......................................................2-25
Entry Lighting.................................................3-39
Event Data Recorders (EDR)............................. 7-8
Extender, Safety Belt.......................................1-26
Exterior Lighting Battery Saver..........................3-38
F
Filter
Engine Air Cleaner......................................5-24
Finish Damage.............................................5-101
Flashers, Hazard Warning.................................. 3-6Flash-to-Pass.................................................3-12
Flat Tire........................................................5-81
Flat Tire, Changing.........................................5-83
Flat Tire, Storing.............................................5-92
Fluid
Automatic Transmission................................5-26
Power Steering...........................................5-39
Windshield Washer......................................5-40
Fog Lamp Light..............................................3-71
Fog Lamps ....................................................3-37
Forward Collision Alert (FAC) System.................. 3-9
Front Axle......................................................5-52
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
Filling a Portable Fuel Container....................5-10
Filling Your Tank........................................... 5-8
Fuels in Foreign Countries.............................. 5-7
Gage .........................................................3-72
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-6
Fuses
Fuses and Circuit Breakers.........................5-105
Rear Underseat Fuse Block.........................5-110
Underhood Fuse Block...............................5-106
Windshield Wiper.......................................5-104
5

G
Gage
Engine Coolant Temperature.........................3-67
Fuel..........................................................3-72
Speedometer..............................................3-59
Tachometer.................................................3-59
Garage Door Opener.......................................2-47
Gasoline
Octane........................................................ 5-5
Specications............................................... 5-6
Glove Box.....................................................2-51
GM Mobility Reimbursement Program.................. 7-5
H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-6
Headlamp Wiring...........................................5-104
Headlamps....................................................3-31
Bulb Replacement.......................................5-53
Daytime Running Lamps...............................3-35
Flash-to-Pass..............................................3-12
Halogen Bulbs............................................5-53
High Intensity Discharge (HID) Lighting...........5-53
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-35Headlamps (cont.)
Washer......................................................3-15
Wiper Activated...........................................3-35
Head-Up Display (HUD)...................................3-40
Heated Seats............................................1-3, 1-4
Heated Steering Wheel..................................... 3-7
Heater...........................................................3-48
Highbeam On Light.........................................3-72
Highway Hypnosis...........................................4-25
Hill and Mountain Roads..................................4-25
Hood
Checking Things Under................................5-10
Release.....................................................5-11
Horn ............................................................... 3-6
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-13
I
Ignition Positions.............................................2-24
Inadvertent Power Battery Saver.......................3-40
Infants and Young Children, Restraints...............1-29
Ination - Tire Pressure...................................5-64
Instrument Panel
Overview..................................................... 3-4
Instrument Panel (I/P)
Brightness..................................................3-39
Cluster.......................................................3-58
6