engine CADILLAC STS V 2007 1.G Owners Manual

Cooling System
When you decide it is safe to lift the hood, this is
what you will see:
A. Engine Cooling Fans
B. Coolant Surge Tank and Pressure CapSome vehicles may have an engine driven fan, as
well as the electric pusher fans which are
located behind the vehicle’s grille.
{CAUTION:
An electric engine cooling fan under the
hood can start up even when the engine
is not running and can injure you. 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.
When the engine is cold, the coolant level
should be at or slightly above the FULL
COLD/FROID line on the side of the coolant surge
tank. If it is not, you may have a leak at the
pressure cap or in the radiator hoses, heater
hoses, radiator, water pump, or somewhere else
in the cooling system.
3.6L V6 Engine shown, 4.6L V8 and 4.4L V8 STS-V
Engines similar
396

{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 is overheating, 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 395for information on
driving to a safe place in an emergency.
Notice:Using coolant other than DEX-COOL
®
may 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 your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
397

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 FULL
COLD/FROID 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 389for 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
CAUTION: (Continued)
CAUTION: (Continued)
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 your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
398

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.
{CAUTION:
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.
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.2. Then keep turning the pressure cap slowly,
and remove it.
399

3. Fill the coolant surge tank with the proper
DEX-COOL®coolant mixture, to slightly
above the FULL COLD/FROID 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 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.
How to Add Coolant to the Intercooler
System Fill Neck (4.4L V8 STS-V
Engine Only)
If you have not found a problem yet, turn the
engine off and allow it to cool down, then check to
see if coolant is visible within the horizontal
tube section of the ll neck. If coolant is not visible,
add a 50/50 mixture of clean, drinkable water
and DEX-COOL
®coolant to the ll neck. Be sure
the Intercooler System, including the Intercooler
System pressure cap, is cool before doing so. See
Engine Coolant on page 389for more information.
400

{CAUTION:
Turning the Intercooler System pressure
cap when the engine and intercooler are
hot can allow steam and scalding liquids
to blow out and burn you badly. Never
turn the Intercooler System pressure cap,
even a little, when the engine and
intercooler are hot.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
CAUTION: (Continued)
CAUTION: (Continued)
engine could get too hot but you would
not get the overheat warning. Your 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.
{CAUTION:
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.
401

1. Remove the Intercooler System pressure cap
when the Intercooler System, including the
upper intercooler hoses, are 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.
This allows any pressure still left to be vented.
2. Then keep turning the pressure cap slowly,
and remove it.3. Add the proper DEX-COOL
®coolant mixture
to the ll neck, until the coolant reaches the
COLD FILL line on the ll neck.
4. 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.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
If the coolant is not at the proper level
when the system cools down again, see
your dealer.
402

Power Steering Fluid
SeeEngine
Compartment Overview
on page 373for
reservoir location.
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 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
uid level on the dipstick.
The level should be within the HOT mark. If
necessary, add only enough uid to bring the
level within the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 516.
Always use the proper uid. Failure to use the
proper uid can cause leaks and damage hoses
and seals.
403

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 CHECK WASHER FLUID message will
appear on the Driver Information Center (DIC)
when the uid level is low. SeeDIC Warnings and
Messages on page 264for more information.
Open the cap with the
washer symbol on it.
Add washer uid
until the tank is full. See
Engine Compartment
Overview on page 373
for 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 your washer uid tank only
three-quarters full when it is very cold.
This allows for 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
your washer system and paint.
404

Brakes
Brake Fluid
Your brake master
cylinder reservoir is
lled with DOT-3 brake
uid. SeeEngine
Compartment Overview
on page 373for
reservoir location
and access.
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 system. If it is, you should have your
brake system xed, since a leak means that
sooner or later your brakes will not work well, or
will not work at all.So, it is not a good idea to top off your brake uid.
Adding brake uid will not correct a leak. If you
add uid when your linings are worn, then you will
have too much uid when you get new brake
linings. You should 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 on and the brake uid is low, the
CHECK BRAKE FLUID message will be
displayed in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 264.
405