2003 BUICK CENTURY engine

If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:
·Reducing vehicle speed.
·Avoiding hard accelerations.
·Avoiding steep uphill grades.
·If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops ¯ashing and remains on steady, see ªIf
the Light Is On Steadyº following.
If the light continues to ¯ash, when it is safe to do so,
stop the vehicle.Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see ªIf
the Light Is On Steadyº following. If the light is still
¯ashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. See
Filling Your Tank on page 5-7. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, mis®ring, hesitation
on acceleration or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
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If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to ®x any
mechanical or electrical problems that may have
developed.
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the SERVICE
ENGINE SOON light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
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Oil Pressure Light
If you have a problem with
your oil, this light may stay
on after you start your
engine, or come on when
you are driving.
This indicates that oil is not going through your engine
quickly enough to keep it lubricated. The engine
could be low on oil or could have some other oil
problem. Have it ®xed right away.
The oil light could also come on in the following
situations:
·The light will come on brie¯y when you turn on the
ignition to show you that it is working properly. If it
doesn't come on with the ignition on, you may
have a problem with the fuse or bulb. Have it ®xed
right away.
·Sometimes when the engine is idling at a stop, the
light may blink on and off. This is normal.
{CAUTION:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches ®re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
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Low Oil Level Light
If your vehicle is equipped
with an oil level monitoring
system, the LOW OIL
light will come on brie¯y
when the ignition key
is turned on.
If the light does not come on brie¯y, have it ®xed so it
will be ready to warn you if there's a problem.
If the light stays on, stop the vehicle on a level surface
and turn the engine off. Check the oil level using the
engine oil dipstick. See
Engine Oil on page 5-13.Ifthe
light does not come on brie¯y, have the low oil level
sensor system repaired so it will be ready to warn you if
there's a problem.
The oil level monitoring system only checks oil level
during the brief period between key on and engine
crank. It does not monitor engine oil level when
the engine is running. Additionally, an oil level check is
only performed if the engine has been turned off for
a considerable period of time, allowing the oil normally
in circulation to drain back into the oil pan.
Change Engine Oil Light
The CHANGE OIL SOON
light should come on
brie¯y as a bulb check
when you start the engine.
If the light doesn't come
on, have it serviced.
If the CHANGE OIL SOON light comes on and stays on
after you start the engine, have the oil changed.
For additional information, see ªWhen to Change Engine
Oil (GM Oil Life System)º under
Engine Oil on page 5-13.
To reset the CHANGE OIL SOON light, see ªHow to
Reset the Systemº under
Engine Oil on page 5-13.
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Audio System(s)
Notice:Before you add any sound equipment to
your vehicle ± like a tape player, CB radio, mobile
telephone or two-way radio ± be sure you can
add what you want. If you can, it's very important to
do it properly. Added sound equipment may
interfere with the operation of your vehicle's engine,
radio or other systems, and even damage them.
Your vehicle's systems may interfere with the
operation of sound equipment that has been added
improperly.
So, before adding sound equipment, check with
your dealer and be sure to check federal rules
covering mobile radio and telephone units.
Your audio system has been designed to operate easily
and to give years of listening pleasure. You will get
the most enjoyment out of it if you acquaint yourself with
it ®rst. Figure out which radio you have in your vehicle,®nd out what your audio system can do and how to
operate all of its controls to be sure you're getting the
most out of the advanced engineering that went into it.
Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, you can play your audio
system even after the ignition is turned off. See
ªRetained Accessory Power (RAP)º under
Ignition
Positions on page 2-19.
Setting the Time
Press and hold HRS until the correct hour appears on
the display. Press and hold MIN until the correct minute
also appears.
You may set the time with the ignition off if you push
RECALL ®rst.
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Avoid needless heavy braking. Some people drive in
spurts Ð heavy acceleration followed by heavy
braking Ð rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you're driving, brake
normally but don't pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.Anti-lock Brake System (ABS)
Your vehicle may have anti-lock brakes. ABS is an
advanced electronic braking system that will help
prevent a braking skid.
If your vehicle has anti-lock brakes, this warning light on
the instrument panel will come on brie¯y when you
start your vehicle.
When you start your engine, or when you begin to drive
away, your anti-lock brake system will check itself.
You may hear a momentary motor or clicking noise while
this test is going on, and you may even notice that
your brake pedal moves or pulses a little. This is normal.United States
Canada
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Enhanced Traction System (ETS)
Your vehicle may have an Enhanced Traction System
(ETS) that limits wheel spin. This is especially useful in
slippery road conditions. The system operates only if
it senses that one or both of the front wheels are
spinning or beginning to lose traction. When this
happens, the system reduces engine power and may
also upshift the transaxle to limit wheel spin.
This light will come on the
instrument panel cluster
while the Enhanced
Traction System is limiting
wheel spin. See
Enhanced
Traction System Warning
Light on page 3-28
.
You may feel or hear the system working, but this is
normal.
If your vehicle is in cruise control when the enhanced
traction system begins to limit wheel spin, the cruise
control will automatically disengage. When road
conditions allow you to safely use it again, you may
re-engage the cruise control. See ªCruise Controlº under
Turn Signal/Multifunction Lever on page 3-5.The Enhanced Traction System operates in THIRD (3)
and OVERDRIVE (
X). If you are in THIRD (3), the
system can upshift the transaxle to OVERDRIVE (
X).
The Enhanced Traction System is turned off in
SECOND (2) or FIRST (1) gear. See
Automatic
Transaxle Operation on page 2-23.
While the system is on,
this warning light will come
on the instrument panel
cluster to let you know
if there is a problem.
See
Enhanced Traction System Warning Light on
page 3-28. While this warning light is on, the system will
not limit wheel spin. Adjust your driving accordingly.
To limit wheel spin, especially in slippery road
conditions, you should always leave the Enhanced
Traction System on. But you can turn the system off if
you ever need to. You should turn the system off if
the vehicle ever gets stuck in sand, mud or snow and
rocking the vehicle is required. See ªRocking Your
Vehicle To Get It Outº under
If You Are Stuck: In Sand,
Mud, Ice or Snow on page 4-31.
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To turn the system off, move the gear shift lever to
FIRST (1) or SECOND (2) gear. See ªRocking Your
Vehicle To Get It Outº under
If You Are Stuck: In Sand,
Mud, Ice or Snow on page 4-31. When you turn the
system off, the Enhanced Traction System warning light
will come on and stay on. If the Enhanced Traction
System is limiting wheel spin when you turn the system
off, the warning light will come on ± but the system won't
turn off right away. It will wait until there's no longer a
current need to limit wheel spin. Also, if you set the
parking brake, the system will turn off.
You can turn the system back on at any time by shifting
to OVERDRIVE (
X) or THIRD (3). The Enhanced
Traction System warning light should go off.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer
but it will take much more effort.
Steering Tips
Driving on Curves
It's important to take curves at a reasonable speed.
A lot of the ªdriver lost controlº accidents mentioned on
the news happen on curves. Here's why:
Experienced driver or beginner, each of us is subject to
the same laws of physics when driving on curves.
The traction of the tires against the road surface makes
it possible for the vehicle to change its path when
you turn the front wheels. If there's no traction, inertia
will keep the vehicle going in the same direction. If
you've ever tried to steer a vehicle on wet ice, you'll
understand this.
The traction you can get in a curve depends on the
condition of your tires and the road surface, the angle at
which the curve is banked, and your speed. While you're
in a curve, speed is the one factor you can control.
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