2008 CADILLAC CTS engine

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Electric Engine Cooling Fans (Out of View)
B. Coolant Surge Tank and Pressure Cap{CAUTION:
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 the coolant inside the coolant surge tank is boiling,
do not do anything else until it cools down. The vehicle
should be parked on a level surface.
If the engine is warm or hot, the coolant level should be
at or above the FROID/FULL COLD line on the side of the
coolant surge tank. If the engine is cold, the coolant level
should be near the FROID/FULL COLD line on the side of
the coolant surge tank. If it is not, you could have a leak
at the pressure cap or in the radiator hoses, heater
hoses, radiator, water pump, or somewhere else in
the cooling system.
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{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them.
If you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.
If there seems to be no leak, with the engine on, check
to see if the electric engine cooling fans are running.
If the engine hot light is on, both fans should be running.
If they are not, your vehicle needs service.Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
SeeOverheated Engine Protection Operating Mode
on page 5-33for information on driving to a safe
place in an emergency.
Notice:Using coolant other than DEX-COOL®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in
the vehicle.
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How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible but
the coolant level is not at the FROID/FULL COLD line on
the side of the coolant surge tank, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant at the
coolant surge tank, but be sure the cooling system,
including the coolant surge tank pressure cap, is cool
before you do it. SeeEngine Coolant on page 5-28for
more information.
{CAUTION:
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.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The engine
could catch re and you or others could be
burned. Use a 50/50 mixture of clean, drinkable
water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
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{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains eythylene glycol
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
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 turn and then stop.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.2. Then keep turning the pressure cap slowly, and
remove it.
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3. Fill the coolant surge tank with the proper mixture,
to slightly above the FROID/FULL COLD line on the
side of the coolant surge tank.4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. The upper radiator hose is
the top hose coming out of the radiator, on the
passenger’s 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 FROID/FULL COLD
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.
Recheck the coolant level in the bottle next time you
use your vehicle to insure the system is full when cold.
SeeEngine Coolant on page 5-28.
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Power Steering Fluid
SeeEngine Compartment
Overview on page 5-14for
the location of the power
steering uid reservoir.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid 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 uid, do the following:
1. Turn the key 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 uid level on
the dipstick.
The level should be at the FULL COLD mark.
If necessary, add only enough uid to bring the level
up to the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-14.
Always use the proper uid.
Notice:Use of the incorrect uid may damage your
vehicle and the damages may not be covered by
your warranty. Always use the correct uid listed in
Recommended Fluids and Lubricants on page 6-14.
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Windshield Washer Fluid
What to Use
When you need windshield washer uid, 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 uid that has sufficient
protection against freezing.
Adding Washer Fluid
The Washer Fluid Low Add Fluid message will appear
on the Driver Information Center (DIC) when the uid
level is low. SeeDIC Warnings and Messages on
page 3-56for more information.
Open the cap with the
washer symbol on it.
Add washer uid until the
tank is full. SeeEngine
Compartment Overview
on page 5-14for reservoir
location.Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts of
the washer system. Also, water does not clean as
well as washer uid.
Fill the washer uid tank only three-quarters
full when it is very cold. This allows for uid
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage the vehicle’s
windshield washer system and paint.
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Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-14for
the location of the reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down. The rst is that the brake
uid goes down to an acceptable level during normal
brake lining wear. When new linings are put in, the uid
level goes back up. The other reason is that uid is
leaking out of the brake hydraulic system. If it is, have
the brake hydraulic system xed, since a leak means
that sooner or later the brakes will not work well.Do not top off the brake uid. Adding brake uid will not
correct a leak. If uid is added when the linings are
worn, there will be too much uid when new brake
linings are installed. Add or remove brake uid, as
necessary, only when work is done on the brake
hydraulic system.
{CAUTION:
If your vehicle has too much brake uid, it can
spill on the engine. The uid will burn if the
engine is hot enough. You or others could be
burned, and your vehicle could be damaged.
Add brake uid only when work is done on
the brake hydraulic system.
If the ignition is in ON/RUN and the brake uid is low,
the Service Brake System message will be displayed in
the DIC. SeeDIC Warnings and Messages on page 3-56.
When the brake uid falls to a low level, the brake
warning light will come on. SeeBrake System Warning
Light on page 3-38.
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