2005 CADILLAC DEVILLE engine

If Steam Is Coming From Your Engine
{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. Just 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 your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
SeeOverheated Engine Protection Operating
Mode on page 5-29for information on driving
to a safe place in an emergency.Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty. SeeOverheated Engine
Protection Operating Mode on page 5-29for
information on driving to a safe place in an
emergency.
If No Steam Is Coming From Your
Engine
An overheat warning, along with a low coolant message,
can indicate a serious problem.
If you get an engine overheat warning with no low
coolant message, but see or hear no steam, the problem
may not be too serious. Sometimes the engine can
get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
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If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Set the climate controls to the highest heat setting
and fan speed and open the windows as necessary.
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for about
10 minutes. If the warning does not come back on, you
can drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there is still no sign of steam, idle the engine for three
minutes while you are parked. If you still have the
warning,turn off the engine and get everyone out of the
vehicleuntil it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
message ENGINE OVERHEATED, STOP ENGINE is
displayed, an overheat protection mode which alternates
ring groups of cylinders helps prevent engine damage.
In this mode, you will notice a loss in power and
engine performance. This operating mode allows your
vehicle to be driven to a safe place in an emergency.
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, change the oil and
reset the oil life system. SeeEngine Oil on
page 5-14.
5-29

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Surge Tank with Pressure Cap
B. Electric Engine Cooling Fans{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.
A low coolant level should be indicated by a CHECK
COOLANT LEVEL message on the Driver Information
Center (DIC). If it is, 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.
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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 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. See
Overheated Engine Protection Operating Mode on
page 5-29for 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 may
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.
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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 level is not 4.5 inches (11.4 cm) below the top of
the ller neck, add a 50/50 mixture ofclean, drinkable
waterand 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 5-24for more
information.If no coolant is visible in the surge tank, add coolant
as follows:
{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.
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{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.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.
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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. 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 about 4.5 inches (11.4 cm)
from the top of the ller neck.
5. Then replace the pressure cap. Be sure the arrow
on the pressure cap lines up with the tube.Start the engine and allow it to warm up. If the CHECK
COOLANT LEVEL message does not appear on the
Driver Information Center (DIC), coolant is at the proper
ll level. If a CHECK COOLANT LEVEL message
does appear, repeat Steps 1 to 3 then reinstall the
pressure cap, or see your dealer.
Power Steering Fluid
The power steering uid
reservoir is located next to
the underhood fuse
block on the passenger’s
side of the vehicle.
SeeEngine Compartment
Overview on page 5-12
for more information
on 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.
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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 6-12.
Always use the proper uid. Failure to use the proper
uid can cause leaks and damage hoses and seals.
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 be
displayed on the Driver Information Center (DIC) when
the uid is low.
Open the cap with the
washer symbol on it.
Add washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-12for reservoir
location.
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