engine BUICK LACROSSE 2007 Owner's Manual

Engine Coolant
The cooling system in the vehicle is lled with
DEX-COOL®engine coolant. This coolant
is designed to remain in the vehicle for ve years
or 150,000 miles (240 000 km), whichever
occurs rst, if only DEX-COOL
®extended life
coolant is added.
The following explains the cooling system and
how to add coolant when it is low. If there is
a problem with engine overheating or if coolant
needs to be added to the radiator, seeEngine
Overheating on page 367.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®engine coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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 the rst
maintenance service after each 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.
363

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 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 470for more information.
364

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 350for 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
recovery tank and has an arrow pointing
down at it.
3.8L V6 Engine shown,
3.6L V6 Engine
similar
365

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 367.
{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 370.
366

Radiator 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.
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 350for 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. See
Engine Coolant Temperature Gage on page 189
andEngine Coolant Temperature Warning Light
on page 188for 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 208for more information.
367

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. 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 the vehicles
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.
CAUTION: (Continued)
CAUTION: (Continued)
SeeOverheated Engine Protection
Operating Mode on page 370for
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. See
Overheated Engine Protection Operating Mode
on page 370for information on driving to a
safe place in an emergency.
368

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 vehicle until 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.
369

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), if the
vehicle has one, 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 353.
Cooling System
When you decide it is safe to lift the hood, this is
what you will see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Electric Engine Cooling Fans
3.8L V6 Engine
370

A. Coolant Recovery Tank
B. Pressure Cap
C. 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 recovery tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.
3.6L V6 Engine
371

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. SeeOverheated Engine Protection
Operating Mode on page 370for 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.
372