2011 CADILLAC STS engine

Black plate (27,1)Cadillac STS Owner Manual - 2011
Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
The coolant surge tank and pressure cap are located on
the driver's side of the vehicle, toward the rear of the
engine compartment. SeeEngine Compartment
Overview
on page 6‑13for more information on
location. Check to see if coolant is visible in the coolant surge
tank. If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
If coolant is visible but the coolant level is not at or
above the FULL COLD/FROID line, add a 50/50 mixture
of clean, drinkable water and DEX-COOL
®coolant at
the coolant surge tank, but be sure the cooling system
is cool before this is done.
When the engine is cold, the coolant level should be at
or above the FULL COLD/FROID line on the side of the
coolant surge tank. Follow the arrow from the top of the
tank down the side to the horizontal mark. If it is not,
there could be a leak in the cooling system.
If the coolant is low, add the coolant or take the vehicle
to a dealer for service
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Black plate (28,1)Cadillac STS Owner Manual - 2011
How to Add Coolant to the Surge Tank
{WARNING:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot enough.
Do not spill coolant on a hot engine.
{WARNING:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They are
under pressure, and if you turn the coolant surge
tank pressure cap—even a little —they can come
out at high speed. Never turn the cap when the
cooling system, including the coolant surge tank
pressure cap, is hot. Wait for the cooling system
and coolant surge tank pressure cap to cool if you
ever have to turn the pressure cap.
{WARNING:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can cause injury. Keep hands, clothing, and tools
away from any underhood electric fan.
If no coolant is visible in the surge tank, add coolant as
follows: 1. Remove the coolant surge tank pressure cap when the cooling system, including the coolant surge
tank pressure cap and upper radiator hose, is
no longer hot. Turn the pressure cap slowly
counterclockwise about one-quarter of a turn.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
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Black plate (30,1)Cadillac STS Owner Manual - 2011
4. With the coolant surge tank pressure cap off, startthe engine and let it run until you can feel the
upper radiator hose getting hot. The upper radiator
hose is the largest of the hoses which comes out
of the radiator, on the passenger side of the
vehicle. Watch out for the engine cooling fans.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge
tank until the level reaches the FULL COLD/FROID
line on the side of the coolant surge tank.
5. Then replace the pressure cap. Be sure the pressure cap is hand-tight and fully seated.
Start the engine and allow it to warm up.
Engine Overheating
The vehicle has several indicators to warn of engine
overheating.
There are two engine hot messages that could be
displayed in the Driver Information Center (DIC). See
DIC Warnings and Messages
on page 4‑76DIC
Warnings and Messages for more information. If the engine is overheating, then you will find a coolant
temperature gauge and a coolant warning light on the
instrument panel. See
Engine Coolant Temperature
Gauge
on page 4‑61and Engine Coolant Temperature
Warning Lighton page 4‑61for more information.
You may decide not to lift the hood when this warning
appears, but instead get service help right away. See
Roadside Service on page 8‑8.
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 your engine
without coolant is not covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode for information on driving to a safe
place in an emergency.
Notice: If the engine catches fire while driving with
no coolant, the vehicle can be badly damaged. The
costly repairs would not be covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode
on page 6‑32for information on
driving to a safe place in an emergency.
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Black plate (31,1)Cadillac STS Owner Manual - 2011
If Steam Is Coming From The Engine
Compartment
{WARNING:
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 fire. 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 6‑32for information on driving to
a safe place in an emergency.
If No Steam Is Coming From The
Engine Compartment
An overheat warning, can indicate a serious problem.
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer.
If the overheat warning is displayed with no sign of
steam: 1. Turn the air off.
2. Turn the heater on to the highest temperature and to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral) while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let the
engine idle.
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Black plate (32,1)Cadillac STS Owner Manual - 2011
If the engine coolant temperature gauge is no longer in
the overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down. Also,
see "Overheated Engine Protection Operating Mode"
later in this section.Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Should an overheated
engine condition exist, an overheat protection mode
which alternates firing groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss in
power and engine performance. An engine overheat
warning will indicate that an overheat condition exists.
Driving extended miles (km) and/or towing a trailer in
the overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss and change the oil.
See Engine Oil on page 6‑16.
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Black plate (33,1)Cadillac STS Owner Manual - 2011
Power Steering Fluid
SeeEngine Compartment
Overviewon page 6‑13for reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there is a leak in the system or
you hear an unusual noise. A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How to Check Power Steering Fluid
To check the power steering fluid, do the following:
1. Turn the ignition off and let the engine compartment cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the fluid level on the dipstick.
The level should be within the HOT mark. If necessary,
add only enough fluid to bring the level within the mark.
What to Use
To determine what kind of fluid to use, see
Recommended Fluids and Lubricantson page 7‑9.
Always use the proper fluid.
Notice: Use of the incorrect fluid may damage the
vehicle and the damages may not be covered by the
vehicle's warranty. Always use the correct fluid
listed in Recommended Fluids and Lubricants
on
page 7‑9.
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Black plate (34,1)Cadillac STS Owner Manual - 2011
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to
read the manufacturer's instructions before use. If you
will be operating your vehicle in an area where the
temperature may fall below freezing, use a fluid that has
sufficient protection against freezing.
Adding Washer Fluid
The CHECK WASHER FLUID message will appear on
the Driver Information Center (DIC) when the fluid level
is low. SeeDIC Warnings and Messages
on page 4‑76for more information.
Open the cap with the
washer symbol on it.
Add washer fluid until the
tank is full. See Engine
Compartment Overview
on page 6‑13for
reservoir location.
Notice:
.When using concentrated washer fluid,
follow the manufacturer's instructions for
adding water.
.Do not mix water with ready-to-use washer
fluid. Water can cause the solution to freeze
and damage the washer fluid tank and other
parts of the washer system. Also, water does
not clean as well as washer fluid.
.Fill the washer fluid tank only three-quarters
full when it is very cold. This allows for fluid
expansion if freezing occurs, which could
damage the tank if it is completely full.
.Do not use engine coolant (antifreeze) in
the windshield washer. It can damage the
windshield washer system and paint.
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Black plate (35,1)Cadillac STS Owner Manual - 2011
Brakes
Brake Fluid
The brake master cylinder
reservoir is filled with DOT
3 brake fluid. SeeEngine
Compartment Overview
on page 6‑13for
reservoir location and
access.
There are only two reasons why the brake fluid level in
the reservoir might go down:
.The brake fluid level goes down because of
normal brake lining wear. When new linings are
installed, the fluid level goes back up.
.A fluid leak in the brake hydraulic system can also
cause a low fluid level. Have the brake hydraulic
system fixed, since a leak means that sooner or
later the brakes will not work well. Do not top off the brake fluid. Adding fluid does not
correct a leak. If fluid is added when the linings are
worn, there will be too much fluid when new brake
linings are installed. Add or remove brake fluid, as
necessary, only when work is done on the brake
hydraulic system.
{WARNING:
If too much brake fluid is added, it can spill on the
engine and burn, if the engine is hot enough. You
or others could be burned, and the vehicle could
be damaged. Add brake fluid only when work is
done on the brake hydraulic system.
If the ignition is on and the brake fluid is low, the
CHECK BRAKE FLUID message displays in the Driver
Information Center (DIC). See DIC Warnings and
Messages on page 4‑76.
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