engine overheat BUICK LACROSSE 2005 User Guide

What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®engine coolant which will
not damage aluminum parts. If this coolant mixture is
used, nothing else needs to be added.
{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:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.If coolant needs to be added more than four times a
year, have your dealer check the cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant recovery tank
is located in the engine
compartment toward
the rear of the engine on
the passenger’s side of the
vehicle. SeeEngine
Compartment Overview on
page 5-12for more
information on location.
The vehicle must be on a level surface when checking
the coolant level.
When the engine is cold, the coolant level should be at
the cold ll line or a little higher. The cold ll line is
near the bottom of the surge tank and has an arrow
pointing down at it.3.8L V6 engine shown,
3.6L V6 engine similar
5-22

Adding Coolant
If more coolant is needed, add the proper DEX-COOL®
coolant mixture at the coolant recovery tank, but be
careful not to spill it.
If the coolant recovery tank is completely empty, add
coolant to the radiator. SeeEngine Overheating
on page 5-24.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the
radiator. Never turn the radiator pressure
cap — even a little — when the engine and
radiator are hot.
{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.
Occasionally check the coolant level in the radiator. For
information on how to add coolant to the radiator,
seeCooling System on page 5-26.
5-23

Radiator Pressure Cap
Notice:The radiator cap on your vehicle is a
pressure-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating. Be sure the arrows on the cap line
up with the overow tube on the radiator ller neck.
The radiator pressure cap is located in the front of the
engine compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 5-12for more information on location.
Engine Overheating
There is a coolant temperature gage and a warning light
on the instrument panel cluster that indicate an
overheated engine condition. SeeEngine Coolant
Temperature Gage on page 3-38andEngine Coolant
Temperature Warning Light on page 3-38for more
information.
In addition, if your vehicle is equipped with a Driver
Information Center (DIC), you will nd an ENGINE
COOLANT HOT and a REDUCED POWER STOP
WHEN SAFE message displayed on the DIC. SeeDIC
Warnings and Messages on page 3-53for more
information.
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 5-26for information on driving
to a safe place in an emergency.
5-24

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 5-26for
information on driving to a safe place in an
emergency.
If No Steam Is Coming From
Your Engine
If you get an engine overheat warning, 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.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 is 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 and you have not stopped, pull
over, stop, and park your vehicle right away.
If there is still no sign of steam, you can 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.
5-25

Overheated Engine Protection
Operating Mode
This emergency operating mode allows your vehicle to
be driven to a safe place in an emergency situation. If an
overheated engine condition exists, an overheat
protection mode which alternates ring groups of
cylinders helps prevent engine damage. In this mode, you
will notice a signicant loss in power and engine
performance. The REDUCED POWER STOP WHEN
SAFE message will come on in the Driver Information
Center (DIC), along with the engine coolant temperature
warning light on the instrument panel, to indicate the
vehicle has entered overheated engine protection
operating mode. The temperature gage will also indicate
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, change the oil and reset the oil
life system. SeeEngine Oil on page 5-15.
Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Electric Engine Cooling Fans3.8L V6 engine
5-26

When the engine is cold, the coolant level should be at
or above the cold ll line on the coolant recovery
tank. If it is not, there may be a leak at the pressure cap
or in the radiator hoses, heater hoses, radiator, water
pump, or somewhere else in the cooling system.
{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, the fans should be running.
If the fans are not running, the 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 5-26for 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.
5-28

How to Add Coolant to the Coolant
Recovery Tank
{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.If you have not found a problem yet, but the coolant
level is not at the cold ll line, add a 50/50 mixture
ofclean, drinkable waterand DEX-COOL
®engine
coolant at the coolant recovery tank. SeeEngine
Coolant on page 5-21for more information.
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.
When the coolant level in the coolant recovery tank is at
the cold ll line, start the vehicle.
5-29

If the overheat warning continues, there is one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the system
is cool before you do it.
{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 radiator
pressure cap — even a little — they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
How to Add Coolant to the Radiator
Notice:Your engine has a specic radiator
ll procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
1. You can remove the
radiator pressure cap
when the cooling
system, including the
radiator pressure
cap and upper radiator
hose, is no longer
hot. Turn the pressure
cap slowly
counterclockwise until it
rst stops.
Do not press down while turning the pressure cap.
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, but now push
down as you turn it. Remove the pressure cap.
5-30

Electrical System (cont.)
Power Windows and Other Power Options......5-88
Underhood Fuse Block.................................5-90
Windshield Wiper Fuses...............................5-87
Engine
Air Cleaner/Filter.........................................5-19
Battery.......................................................5-38
Change Engine Oil Light...............................3-43
Check and Service Engine Soon Light............3-39
Coolant......................................................5-21
Coolant Heater............................................2-23
Coolant Temperature Gage...........................3-38
Coolant Temperature Warning Light................3-38
Engine Compartment Overview......................5-12
Exhaust.....................................................2-30
Oil .............................................................5-15
Oil Life System...........................................5-18
Overheated Protection Operating Mode...........5-26
Overheating................................................5-24
Reduced Power Light...................................3-44
Starting......................................................2-22
Entry Lighting.................................................3-16
Event Data Recorders (EDR)............................. 7-9
Extender, Safety Belt.......................................1-30
Exterior Lamps...............................................3-13
Exterior Lighting Battery Saver..........................3-15F
Filter
Engine Air Cleaner......................................5-19
Finish Damage...............................................5-84
Flash-to-Pass................................................... 3-8
Flat Tire........................................................5-67
Flat Tire, Changing.........................................5-68
Flat Tire, Storing.............................................5-76
Fluid
Automatic Transmission................................5-21
Power Steering...........................................5-33
Windshield Washer......................................5-34
Fog Lamps............................................3-15, 5-48
Folding Rear Seat............................................ 1-8
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
Check Gas Cap Light...................................3-46
Filling a Portable Fuel Container....................5-10
Filling Your Tank........................................... 5-8
Fuels in Foreign Countries.............................. 5-7
Gage.........................................................3-46
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-6
Low Warning Light.......................................3-46
5

Mirrors (cont.)
Outside Power Heated Mirrors.......................2-34
Outside Power Mirrors..................................2-33
MyGMLink.com................................................ 7-3
N
New Vehicle Break-In......................................2-21
Normal Maintenance Replacement Parts............6-13
O
Odometer......................................................3-32
Off-Road Recovery..........................................4-12
Oil
Change Engine Oil Light...............................3-43
Engine.......................................................5-15
Pressure Light.............................................3-42
Oil, Engine Oil Life System..............................5-18
Older Children, Restraints................................1-31
Online Owner Center........................................ 7-3
OnStar
®System.............................................2-34
Other Warning Devices...................................... 3-6
Outlet Adjustment............................................3-28
Outside
Convex Mirror.............................................2-34
Power Heated Mirrors..................................2-34
Power Mirrors.............................................2-33Overhead Console Reading Lamps....................3-18
Overheated Engine Protection
Operating Mode..........................................5-26
Owner Checks and Services.............................. 6-8
Owners, Canadian............................................... ii
P
Park Aid........................................................3-18
Park (P)
Shifting Into................................................2-28
Shifting Out of............................................2-29
Parking
Assist........................................................3-18
Brake........................................................2-27
Over Things That Burn.................................2-30
Passenger Airbag Status Indicator.....................3-34
Passenger Compartment Air Filter.....................3-28
Passenger Sensing System..............................1-60
Passing.........................................................4-12
PASS-Key
®III ................................................2-19
PASS-Key®III Operation..................................2-19
Perimeter Lighting...........................................3-18
Power
Accessory Outlets........................................3-20
Door Locks.................................................2-11
Electrical System.........................................5-88
9