2005 BUICK CENTURY oil temperature

Engine Coolant Heater
Your vehicle may be equipped with this feature. In very
cold weather, 0°F (−18°C) or colder, the engine coolant
heater can help. You will get easier starting and better
fuel economy during engine warm-up. Usually, the
coolant heater should be plugged in a minimum of four
hours prior to starting your vehicle. At temperatures
above 32°F (0°C), use of the coolant heater is
not required.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is attached to the underside of the
diagonal brace, which is located above the engine
air cleaner/lter assembly.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could
be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer in the area where you will be parking
your vehicle. The dealer can give you the best advice
for that particular area.
2-20

Notice:Use only engine oil identied as meeting
GM Standard GM6094M and showing the American
Petroleum Institute Certied For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
®oil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all you will need for good performance
and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and lter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE OIL SOON light will come on.
Change your oil as soon as possible within the next
two times you stop for fuel. It is possible that, if you are
driving under the best conditions, the oil life system
may not indicate that an oil change is necessary for over
a year. However, your engine oil and lter must be
changed at least once a year and at this time the system
must be reset. Your dealer has GM-trained service
people who will perform this work using genuine GM
parts and reset the system. It is also important to check
your oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must change
your oil at 3,000 miles (5 000 km) since your last oil
change. Remember to reset the oil life system whenever
the oil is changed.
5-16

{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned.
The air cleaner not only cleans the air;
it helps to stop ame if the engine backres.
If it is not there and the engine backres,
you could be burned. Do not drive with it off,
and be careful working on the engine with the
air cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre
can cause a damaging engine re. And, dirt
can easily get into your engine, which will damage
it. Always have the air cleaner/lter in place
when you are driving.
Automatic Transaxle Fluid
When to Check and Change
A good time to check the automatic transaxle uid level
is when the engine oil is changed.
Change both the uid and lter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or
delivery service.
If the vehicle is not used under any of these conditions,
change the uid and lter at 100,000 miles (166 000 km).
SeeScheduled Maintenance on page 6-4.
5-19

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 5 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 5-25.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®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 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.
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 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.
5-22

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

(h)Change automatic transaxle uid and lter if
the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or
delivery service.
(i)Drain, ush and rell cooling system. See Engine
Coolant on page 5-22for what to use. Inspect hoses.
Clean radiator, condenser, pressure cap and ller neck.
Pressure test the cooling system and pressure cap.
(j)Check throttle system for interference or binding
and for damaged or missing parts. Replace parts
as needed. Replace any components that have high
effort or excessive wear. Do not lubricate accelerator or
cruise control cables.
(k)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the uid level checked. Add uid if needed.Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench dealer can assist you
with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel ll.
Engine Oil Level Check
Check the engine oil level and add the proper oil
if necessary. SeeEngine Oil on page 5-13for
further details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
6-9

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

LATCH System
Child Restraints...........................................1-40
Securing a Child Restraint Designed for
the LATCH System...................................1-42
Leaving Your Vehicle.......................................2-12
Light
Airbag Readiness........................................3-31
Anti-Lock Brake System Warning...................3-33
Brake System Warning.................................3-32
Change Engine Oil......................................3-40
Charging System.........................................3-32
Cruise Control.............................................3-41
Door/Trunk Ajar Warning...............................3-42
Engine Coolant Temperature Warning.............3-35
Enhanced Traction System (ETS)
Warning Light..........................................3-34
Low Fuel Warning.......................................3-43
Low Traction...............................................3-34
Low Washer Fluid Warning...........................3-41
Malfunction Indicator....................................3-36
Oil Pressure...............................................3-40
Safety Belt Reminder...................................3-30
Security.....................................................3-41
Service Vehicle Soon...................................3-42
Tire Pressure..............................................3-36
Lighting
Delayed Entry.............................................3-16
Delayed Exit...............................................3-17
Entry.........................................................3-16Lockout Protection..........................................2-12
Locks
Door..........................................................2-10
Leaving Your Vehicle....................................2-12
Lockout Protection.......................................2-12
Power Door................................................2-11
Programmable Automatic Door Locks.............2-11
Loss of Control...............................................4-15
Low Fuel Warning Light...................................3-43
Low Traction Light..........................................3-34
Low Washer Fluid Warning Light.......................3-41
M
Maintenance Schedule
Additional Required Services........................... 6-6
At Each Fuel Fill........................................... 6-9
At Least Once a Month................................6-10
At Least Once a Year..................................6-10
Introduction.................................................. 6-2
Maintenance Footnotes.................................. 6-8
Maintenance Record....................................6-16
Maintenance Requirements............................. 6-2
Normal Maintenance Replacement Parts.........6-14
Owner Checks and Services........................... 6-9
Recommended Fluids and Lubricants.............6-13
Scheduled Maintenance................................. 6-4
Using Your................................................... 6-2
Your Vehicle and the Environment................... 6-2
7