engine overheat BUICK CENTURY 2005 User Guide

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. See “How to Add Coolant to the
Radiator” later in this section.
{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 5-27.
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 near 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.
5-24

Engine Overheating
The coolant temperature gage and the engine coolant
temperature warning light on the instrument panel
can indicate an overheated engine condition.
SeeEngine Coolant Temperature Gage on page 3-35
andEngine Coolant Temperature Warning Light on
page 3-35.
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.
CAUTION: (Continued)
CAUTION: (Continued)
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.
See “Overheated Engine Protection Operating
Mode” underEngine Overheating on page 5-25
for 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” underEngine
Overheating on page 5-25for information on driving
to a safe place in an emergency.
5-25

If No Steam Is Coming From
Your Engine
An overheated engine warning can indicate a
serious problem.
If there is an overheated engine warning and you do not
see or hear any steam, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
If an overheated engine warning appears 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. Adjust the heater to the highest temperature and fan
speed settings and open the window as necessary.
If the overheated engine warnings no longer exist,
you can drive. Just to be safe, drive slower for about
10 minutes. If the warnings do not come back on,
you can drive normally.
If the warning continues, and you have not stopped,
pull over, stop, and park the vehicle right away.If there is still no sign of steam, idle the engine for
three minutes while you are parked. If the warning still
exists,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
The overheated engine protection operating mode allows
the vehicle to be driven to a safe place in an emergency
situation. If an overheated engine condition exists, this
protection mode alternates ring groups of cylinders to
help prevent engine damage. In this mode, there will be
a signicant loss in power and engine performance.
The engine coolant temperature gage indicator will move
to the red area, and the engine coolant temperature
warning light will come on, showing that an overheated
engine condition exists. Driving extended miles (km)
and/or towing a trailer in the overheated engine 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 5-13.
5-26

{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 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” in the Index for 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
If a problem has not been found yet, but the coolant
level is not at the COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®engine
coolant at the coolant recovery tank. SeeEngine
Coolant on page 5-22for 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 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.
When the coolant in the coolant recovery tank is at the
COLD mark, start the vehicle.
5-29

If the overheated engine warnings continue, there is
one more thing that can be done. Add the proper coolant
mixture directly to the radiator, but be sure the cooling
system is cool before this is done.
{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.
Remove the radiator pressure cap when the cooling
system, including the radiator pressure cap and upper
radiator hose, is no longer hot.
1. Turn the pressure cap slowly counterclockwise to
its rst stop. Do not press down while turning the
pressure cap.
If a hiss is heard, wait for it to stop. A hiss means
there is still some pressure left.
5-30

D
Daytime Running Lamps/Automatic
Headlamp System.......................................3-14
Defensive Driving............................................. 4-2
Delayed Entry Lighting.....................................3-16
Delayed Exit Lighting.......................................3-17
Delayed Headlamps........................................3-13
Doing Your Own Service Work........................... 5-4
Dome Lamp...................................................3-16
Door
Locks........................................................2-10
Power Door Locks.......................................2-11
Programmable Automatic Door Locks.............2-11
Trunk Ajar Warning Light..............................3-42
Driver
Position, Safety Belt.....................................1-12
Driving
At Night.....................................................4-16
City...........................................................4-20
Defensive..................................................... 4-2
Drunken....................................................... 4-3
Freeway.....................................................4-21
Hill and Mountain Roads..............................4-24
In Rain and on Wet Roads...........................4-17
Rocking Your Vehicle to Get it Out.................4-31
Winter........................................................4-26
Dual Automatic Climate Control System.............3-21
Dual Climate Control System............................3-18
E
Electrical System
Add-On Equipment......................................5-90
Fuses and Circuit Breakers...........................5-91
Headlamp Wiring.........................................5-91
Instrument Panel Fuse Block.........................5-91
Power Windows and Other Power Options......5-91
Underhood Fuse Block.................................5-94
Windshield Wiper Fuses...............................5-91
Engine
Air Cleaner/Filter.........................................5-18
Battery.......................................................5-39
Change Engine Oil Light...............................3-40
Check and Service Engine Soon Light............3-36
Coolant......................................................5-22
Coolant Heater............................................2-20
Coolant Temperature Gage...........................3-35
Coolant Temperature Warning Light................3-35
Drive Belt Routing.......................................6-15
Engine Compartment Overview......................5-12
Exhaust.....................................................2-27
Oil .............................................................5-13
Overheated Protection Operating Mode...........5-26
Overheating................................................5-25
Starting......................................................2-19
Enhanced Traction System (ETS)........................ 4-9
Warning Light.............................................3-34
Entry Lighting.................................................3-16
4

Malfunction Indicator Light................................3-36
Manual Seats................................................... 1-2
Mirrors
Manual Rearview Mirror................................2-29
Manual Rearview Mirror with OnStar
®.............2-29
Outside Convex Mirror.................................2-30
Outside Power Mirrors..................................2-30
MyGMLink.com................................................ 7-4
N
New Vehicle Break-In......................................2-17
Normal Maintenance Replacement Parts............6-14
O
Odometer......................................................3-30
Odometer, Trip...............................................3-30
Off-Road Recovery..........................................4-13
Oil
Change Engine Oil Light...............................3-40
Engine.......................................................5-13
Pressure Light.............................................3-40
Older Children, Restraints................................1-27
Online Owner Center........................................ 7-4
OnStar
®System.............................................2-31
Other Warning Devices...................................... 3-6Outlet Adjustment............................................3-26
Outside
Convex Mirror.............................................2-30
Power Mirrors.............................................2-30
Overheated Engine Protection
Operating Mode..........................................5-26
Owner Checks and Services.............................. 6-9
Owners, Canadian............................................... ii
P
Park (P)
Shifting Into................................................2-25
Shifting Out of............................................2-26
Parking
Brake........................................................2-24
Over Things That Burn.................................2-27
Passenger Compartment Air Filter.....................3-26
Passing.........................................................4-13
PASS-Key
®II .................................................2-16
Power
Door Locks.................................................2-11
Electrical System.........................................5-91
Retained Accessory (RAP)............................2-19
Seat............................................................ 1-3
Steering Fluid.............................................5-34
Windows....................................................2-15
Programmable Automatic Door Locks.................2-11
8