engine overheat BUICK CENTURY 2002 User Guide

5-11
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty. See ªOverheated
Engine Protection Operating Modeº in the Index.
If No Steam Is Coming From Your Engine
An overheat warning, along with a low coolant light,
can indicate a serious problem. See ªLow Coolant
Lightº in the Index.
If you get an engine overheat warning with no low
coolant light, 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. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
3. If you're in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- AUTOMATIC OVERDRIVE (
).
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for about
10 minutes. If the warning doesn't come back on,
you can drive normally.
If the warning continues, pull over, stop, and park
your vehicle right away.
If there's still no sign of steam, idle the engine for
three minutes while you're parked. If you still have the
warning, turn off the engine and get everyone out of
the vehicle until it cools down. Also, see ªOverheated
Engine Protection Operating Modeº listed previously
in this section.
You may decide not to lift the hood but to get service
help right away.

5-13
When the engine is cold, the coolant level should be at
or above the COLD mark on the coolant recovery tank.
If it isn't, 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. Don't touch them.
If you do, you can be burned.
Don't run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed 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 aren't, your vehicle needs service.
NOTICE:
Engine damage from running your engine
without coolant isn't covered by your warranty.
See ªOverheated Engine Protection Operating
Modeº in the Index.
NOTICE:
When adding coolant, it is important that you
use only DEX
-COOL
(silicate-free) coolant.
If coolant other than DEX-COOL is added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the
use of coolant other than DEX
-COOL
is not
covered by your new vehicle warranty.

5-14 How to Add Coolant to the Coolant
Recovery Tank
If you haven't found a problem yet, but the coolant level
isn't at the COLD mark, add a 50/50 mixture of clean,
drinkable water and DEX
-COOL
engine coolant at the
coolant recovery tank. See ªEngine Coolantº in the
Index for more information.
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 wouldn't
get the overheat warning. Your engine could
catch fire 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.

5-15
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. Don't spill coolant on a hot engine.
When the coolant in the coolant recovery tank is at the
COLD mark, start your vehicle.
If the overheat warning continues, there's 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
CAUTION: (Continued)
CAUTION: (Continued)
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.

5-16 How to Add Coolant to the Radiator
NOTICE:
Your engine has a specific radiator fill 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 first stops. (Don't 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.

5-32
If You're Stuck: In Sand, Mud,
Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you don't want to spin
your wheels too fast. The method known as ªrockingº
can help you get out when you're stuck, but you must
use caution.
CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured.
And, the transaxle or other parts of the vehicle
can overheat. That could cause an engine
compartment fire or other damage. When you're
stuck, spin the wheels as little as possible. Don't
spin the wheels above 35 mph (55 km/h) as shown
on the speedometer.
NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transaxle back and
forth, you can destroy your transaxle.
For information about using tire chains on your vehicle,
see ªTire Chainsº in the Index.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. You should turn
the Enhanced Traction System off. See ªEnhanced Traction
Systemº in the Index. Then shift back and forth
between REVERSE (R) and FIRST (1) or SECOND (2)
gear. The Enhanced Traction System will be turned off in
FIRST (1) or SECOND (2) gear. Spin the wheels as little
as possible. Release the accelerator pedal while you shift, and
press lightly on the accelerator pedal when the transaxle is in
gear. By slowly spinning your wheels in the forward and
reverse directions, you will cause a rocking motion that may
free your vehicle. If that doesn't get you out after a few tries,
you may need to be towed out. If you do need to be towed
out, see ªTowing Your Vehicleº in the Index.

6-19 How to Check
Because this operation can be a little difficult,
you may choose to have this done at the dealership
service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transaxle. Too much can mean that some of the
fluid could come out and fall on hot engine parts
or exhaust system parts, starting a fire. Too little
fluid could cause the transaxle to overheat. Be
sure to get an accurate reading if you check your
transaxle fluid.
Wait at least 30 minutes before checking the transaxle
fluid level if you have been driving:

When outside temperatures are above 90F (32C).

At high speed for quite a while.

In heavy traffic
-- especially in hot weather.

While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is 180F to 200F
(82C to 93C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50F
(10C). If it's colder than 50F (10C), you may
have to drive longer.

6-22
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL
engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL
extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating or if you need to add coolant to your
radiator, see ªEngine Overheatingº in the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL
coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 265F (129C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you
use only DEX
-COOL (silicate-free) coolant.
If coolant other than DEX-COOL is added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the
use of coolant other than DEX
-COOL is not
covered by your new vehicle warranty.

6-23 What to Use
Use a mixture of one-half clean, drinkable water and
one
-half DEX-COOL
coolant which won't damage
aluminum parts. If you use this coolant mixture, you
don't 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 wouldn't
get the overheat warning. Your engine could
catch fire 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 wouldn't 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 the proper coolant, you don't have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.

6-24 Checking Coolant
The engine coolant recovery tank is located on the
passenger's side of the vehicle at the rear of the engine
compartment. See ªEngine Compartment Overviewº in
the Index for more information on location.
The vehicle must be on a
level surface. When your
engine is cold, the coolant
level should be at the
COLD mark or a little
higher. When your engine
is warm, the level should
be up to the HOT mark or
a little higher.
If this LOW COOLANT
light comes on and stays on,
it means you're low on
engine coolant.Adding Coolant
If you need more coolant, 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. See ªEngine Overheatingº in
the Index.
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.