2005 BUICK CENTURY air condition

Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good, and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice:Modications made to the engine,
transaxle, exhaust, intake, or fuel system of your
vehicle or the replacement of the original tires with
other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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California Fuel
If your vehicle is certied to meet California Emission
Standards (see the underhood emission control
label), it is designed to operate on fuels that meet
California specications. If this fuel is not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance may be affected. The malfunction indicator
lamp may turn on and your vehicle may fail a
smog-check test. SeeMalfunction Indicator Lamp on
page 3-36. If this occurs, return to your authorized
GM dealer for diagnosis. If it is determined that
the condition is caused by the type of fuel used,
repairs may not be covered by your warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly.
You should not have to add anything to your fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. General Motors
recommends that you buy gasolines that are advertised
to help keep fuel injectors and intake valves clean. If your
vehicle experiences problems due to dirty injectors or
valves, try a different brand of gasoline.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specications described earlier.
5-6

{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 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.
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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:
With the wrong kind of uid in your brake
system, your brakes may not work well, or they
may not even work at all. This could cause a
crash. Always use the proper brake uid.
Notice:
Using the wrong uid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system parts so
badly that they will have to be replaced. Do not
let someone put in the wrong kind of uid.
If you spill brake uid on your vehicle’s painted
surfaces, the paint nish can be damaged.
Be careful not to spill brake uid on your
vehicle. If you do, wash it off immediately.
SeeAppearance Care on page 5-82.
Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving, except when you are pushing on the
brake pedal rmly.
{CAUTION:
The brake wear warning sound means that soon
your brakes will not work well. That could lead
to an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
your brakes.
5-37

Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and
air conditioning.
Aspect Ratio:The relationship of a tire’s height to
its width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInation - Tire Pressure on page 5-60.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the
U.S. Department of Transportation motor vehicle safety
standards. The DOT code includes the Tire Identication
Number (TIN), an alphanumeric designator which can
also identify the tire manufacturer, production plant,
brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-31.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-31.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-31.
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Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
If you notice unusual tire wear or your vehicle pulling
one way or the other, the alignment may need to
be reset. If you notice your vehicle vibrating when
driving on a smooth road, your wheels may need to
be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.
{CAUTION:
Using the wrong replacement wheels, wheel
bolts or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance and tire or tire chain
clearance to the body and chassis.
SeeChanging a Flat Tire on page 5-70for
more information.
5-67