2009 CADILLAC CTS service

If doing some of your own service work, use the proper
service manual. It tells you much more about how to
service the vehicle than this manual can. To order
the proper service manual, seeService Publications
Ordering Information on page 7-15.
This vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-72.
Keep a record with all parts receipts and list the
mileage and the date of any service work performed.
SeeMaintenance Record on page 6-18.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect the
airow around it. This can cause wind noise and can
affect fuel economy and windshield washer performance.
Check with your dealer/retailer before adding equipment
to the outside of the vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of this vehicle. To help keep the
engine clean and maintain optimum vehicle performance,
we recommend the use of gasoline advertised as TOP
TIER Detergent Gasoline.
The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-114.
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Gasoline Octane
If the vehicle has the 3.6L V6 engine (VIN Code V), use
regular unleaded gasoline with a posted octane rating of
87 or higher. If the octane rating is less than 87, you
might 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, the engine needs service.
If the 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
could choose to use middle grade 89 octane unleaded
gasoline. If the octane rating is less than 87, you might
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, the engine needs service.If the vehicle has the 6.2L supercharged V8 engine
(VIN Code P), 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 might also hear audible spark knock
during acceleration. Rell the tank with premium fuel as
soon as possible to avoid damaging the engine. If you are
using gasoline rated at 91 octane or higher and you hear
heavy knocking, the engine needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM specication
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 5-7
for additional information.
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California Fuel
If the 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, the vehicle will operate
satisfactorily on fuels meeting federal specications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and the
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-43. 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, you should not have to add anything 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 gasolinethat is advertised as TOP TIER Detergent Gasoline. Also,
your dealer/retailer has additives that will help correct and
prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend 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:This 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 the
vehicle warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance of
the emission control system could be affected. The
malfunction indicator lamp might turn on. If this occurs,
return to your dealer/retailer for service.
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Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM standards are all
you need for good performance and engine protection.
Engine oil system ushes are not recommended and
could cause engine damage not covered by the vehicle
warranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that lets you know
when to change the engine oil and lter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A Change Engine Oil Soon message will come on.
SeeDIC Warnings and Messages on page 3-58. Change
the oil as soon as possible within the next 600 miles
(1 000 km). It is possible that, if you are driving under the
best conditions, the oil life system might not indicate that
an oil change is necessary for over a year. However, the
engine oil and lter must be changed at least once a year
and at this time the system must be reset. Your dealer/
retailer has trained service people who will perform this
work using genuine parts and reset the system. It is also
important to check the oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, you must
change the oil at 3,000 miles (5 000 km) since the last
oil change. Remember to reset the oil life system
whenever the oil is changed.
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Automatic Transmission Fluid
How to Check Automatic Transmission
Fluid
It is not necessary to check the transmission uid level.
A transmission uid leak is the only reason for uid loss.
If a leak occurs, take the vehicle to the dealer/retailer
service department and have it repaired as soon as
possible.
There is a special procedure for checking and changing
the transmission uid. Because this procedure is
difficult, it should be done at the dealer/retailer service
department. Contact your dealer/retailer for additional
information or the procedure can be found in the service
manual. To purchase a service manual, seeService
Publications Ordering Information on page 7-15.Notice:Use of the incorrect automatic transmission
uid may damage the vehicle, and the damages
may not be covered by the vehicle’s warranty.
Always use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-14.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the uid listed inRecommended Fluids and
Lubricants on page 6-14.
Manual Transmission Fluid
It is not necessary to check the manual transmission uid
level. A transmission uid leak is the only reason for uid
loss. If a leak occurs, take the vehicle to a dealer/retailer
for service. Have it repaired as soon as possible. You
may also have the uid level checked by your dealer/
retailer when the oil is changed. SeeRecommended
Fluids and Lubricants on page 6-14for the proper uid
to use.
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Hydraulic Clutch
It is not necessary to regularly check clutch uid unless
you suspect there is a leak in the system. Adding
uid will not correct a leak. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
When to Check and What to Use
The hydraulic clutch uid
reservoir cap has this
symbol on it. SeeEngine
Compartment Overview
on page 5-14for reservoir
location.Refer to the Maintenance Schedule for the proper
uid to use. SeeRecommended Fluids and Lubricants
on page 6-14. The uid requires changing every
two years. SeeAdditional Required Services on
page 6-6.
How to Check and Add Fluid
Visually check the clutch uid reservoir to make sure
the uid level is at the MIN (Minimum) line on the side
of the reservoir. The hydraulic clutch uid system should
be kept closed and sealed. Do not remove the cap to
check the uid level or to top-off the uid level. Remove
the cap only when necessary to add the proper uid
until the level reaches the MIN line.
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3. Add the proper DEX-COOL®coolant mixture to the
ll neck until the coolant reaches the COLD FILL
line on the ll neck.
With the intercooler system pressure cap off, start
the engine and let it run for a couple of minutes.
Then turn the engine off. By this time, the coolant
level inside the ll neck may be lower. If the
level drops to where coolant is no longer visible in
the horizontal tube section of the ll neck, with
the engine off add more of the DEX-COOL
®coolant
mixture to the ll neck until the level is again
visible in the horizontal tube section.
4. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may occur.
Be sure the cap is properly and tightly secured.
If the coolant is not at the proper level when the system
cools down again, see your dealer/retailer.
Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may occur.
Be sure the cap is properly and tightly secured.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 5-14for more
information on location.
Engine Overheating
The vehicle has several indicators to warn of engine
overheating.
There are two engine hot messages that may be
displayed in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-58for
more information.
You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Service on page 7-7.
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If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:If the engine catches re while driving with
no coolant, the vehicle can be badly damaged.
The costly repairs would not be covered by
the vehicle warranty. SeeOverheated Engine
Protection Operating Mode on page 5-39for
information on driving to a safe place in an
emergency.If Steam Is Coming From The Engine
Compartment
{CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no sign
of steam or coolant before you open the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch re. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating Mode
on page 5-39for information on driving to a safe
place in an emergency.
5-38