engine overheat BUICK LUCERNE 2006 User Guide

What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you do
not need to add anything else.
{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 you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use extra inhibitors and/or additives
in your vehicle’s cooling system, you could
damage your vehicle. Use only the proper mixture
of the engine coolant listed in this manual for
the cooling system. SeeRecommended Fluids and
Lubricants on page 6-12for more information.
Checking Coolant (3.8L V6 Engine)
This symbol is located on
the cap of the engine
coolant recovery tank.
The engine coolant recovery tank is located in the
engine compartment 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 your
engine is cold, the coolant level should be at FULL
COLD or a little higher. When your engine is warm, the
level should raise.
5-24

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.
SeeEngine Compartment Overview on page 5-12for
more information on location.
Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
SeeEngine Compartment Overview on page 5-12for
more information on location.
Engine Overheating
There is a hot engine warning light as well as an engine
coolant temperature gage on your vehicle’s instrument
panel cluster.
In addition, if your vehicle is equipped with a Driver
Information Center (DIC), you will nd an ENGINE
OVERHEATED IDLE ENGINE, ENGINE HOT A/C
(Air Conditioning) OFF, or a ENGINE OVERHEATEDSTOP ENGINE message displayed on the DIC. See
DIC Warnings and Messages on page 3-56DIC
Warnings and Messages for 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.
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.
5-27

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. Turn on your heater to full hot at the highest 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.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
(4.6L V8 Engine Only)
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 5-15.
5-28

The coolant level should be at or above the FULL
COLD mark when the engine is cold. The coolant level
should be above the FULL COLD mark under normal
operating conditions. 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.
{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.
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.
5-30

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.
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.If you have not found a problem yet, but the coolant
level is not at the FULL COLD mark, add a
50/50 mixture ofclean, drinkable waterand
DEX-COOL
®engine coolant at the coolant recovery
tank. SeeEngine Coolant on page 5-23for more
information.
{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 in the coolant recovery tank is at the
FULL COLD mark, start your vehicle.
5-31

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 cooling
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
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.
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. Remove the
pressure cap.
3. Remove the 3800 Series II V6 engine cover shield
to access the bleed valve.
5-32

{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.
{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
(4.6L V8 Engine Only) on page 5-28for 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.
5-35

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 at the FULL COLD mark located
on the side of the surge tank, add enough of a 50/50
mixture of clean, drinkable water and DEX-COOL
®
coolant at the coolant surge tank to bring the level to
the FULL COLD mark, but be sure the cooling system,
including the coolant surge tank pressure cap (if
equipped), is cool before you do it. SeeEngine Coolant
on page 5-23for 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.
CAUTION: (Continued)
CAUTION: (Continued)
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 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.
5-36

E
Electrical System
Add-On Equipment......................................5-93
Fuses and Circuit Breakers...........................5-93
Power Windows and Other Power Options......5-93
Rear Underseat Fuse Block..........................5-96
Underhood Fuse Block.................................5-94
Engine
Air Cleaner/Filter.........................................5-19
Battery.......................................................5-42
Check and Service Engine Soon Light............3-44
Coolant......................................................5-23
Coolant Heater............................................2-24
Coolant Temperature Gage...........................3-43
Coolant Temperature Warning Light................3-43
Engine Compartment Overview......................5-12
Exhaust.....................................................2-31
Oil .............................................................5-15
Oil Life System...........................................5-18
Overheated Protection Operating Mode...........5-28
Overheating................................................5-27
Starting......................................................2-23
Entry Lighting.................................................3-17
Event Data Recorders (EDR)............................. 7-9
Extender, Safety Belt.......................................1-30
Exterior Lamps...............................................3-14
Exterior Lighting Battery Saver..........................3-16
F
Filter
Engine Air Cleaner......................................5-19
Finish Damage...............................................5-89
Flashers, Hazard Warning.................................. 3-6
Flash-to-Pass................................................... 3-8
Flat Tire........................................................5-72
Flat Tire, Changing.........................................5-72
Flat Tire, Storing.............................................5-81
Fluid
Automatic Transaxle.....................................5-21
Power Steering...........................................5-38
Windshield Washer......................................5-39
Fog Lamp Light..............................................3-48
Fog Lamps ....................................................3-16
Front Reading Lamps......................................3-18
Front Storage Area.........................................2-44
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
Filling a Portable Fuel Container....................5-10
Filling Your Tank........................................... 5-8
Fuels in Foreign Countries.............................. 5-7
Gage .........................................................3-49
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-5
5

N
Navigation/Radio System,
see Navigation Manual.................................3-98
New Vehicle Break-In......................................2-21
Normal Maintenance Replacement Parts............6-13
O
Odometer......................................................3-35
Odometer, Trip...............................................3-35
Off-Road Recovery..........................................4-13
Oil
Engine.......................................................5-15
Pressure Light.............................................3-47
Oil, Engine Oil Life System..............................5-18
Older Children, Restraints................................1-30
Online Owner Center........................................ 7-3
OnStar
®System, see OnStar®Manual...............2-38
Other Warning Devices...................................... 3-6
Outlet Adjustment............................................3-31
Outlet(s), Accessory Power...............................3-21
Outside
Automatic Dimming Heated Mirror..................2-37
Convex Mirror.............................................2-37
Curb View Assist Mirror................................2-36
Power Mirrors.............................................2-36Overheated Engine Protection Operating Mode.....5-28
Owner Checks and Services.............................. 6-9
Owners, Canadian............................................... ii
P
Paint, Damage...............................................5-89
Panic Brake Assist..........................................4-10
Park Aid........................................................3-18
Park (P)
Shifting Into................................................2-29
Shifting Out of............................................2-30
Parking
Assist........................................................3-18
Brake........................................................2-28
Over Things That Burn.................................2-31
Passenger Airbag Status Indicator.....................3-37
Passenger Compartment Air Filter.....................3-31
Passenger Sensing System..............................1-63
Passing.........................................................4-13
PASS-Key
®III+..............................................2-19
PASS-Key®III+ Operation................................2-20
Perimeter Lighting...........................................3-17
Power
Accessory Outlet(s)......................................3-21
Door Locks.................................................2-11
Electrical System.........................................5-93
9