1998 BUICK CENTURY check engine

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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.
NOTICE:
Engine damage from running your engine
without coolant isn't covered by your warranty.
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.
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.

6-
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Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-3 Fuel
6
-5 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-8 Checking Things Under the Hood
6
-11 Engine Oil
6
-15 Engine Air Cleaner/Filter
6
-17 Supercharger Oil
6
-18 Automatic Transaxle Fluid
6
-20 Radiator Pressure Cap
6
-21 Engine Coolant
6
-25 Windshield Washer Fluid
6
-26 Brakes
6
-29 Battery
6
-31 Bulb Replacement6
-39 Tires
6
-47 Appearance Care
6
-48 Cleaning the Inside of Your Vehicle
6
-51 Cleaning the Outside of Your Vehicle
6
-54 Underbody Maintenance
6
-54 Chemical Paint Spotting
6
-55 GM Vehicle Care/Appearance Materials
6
-56 Vehicle Identification Number (VIN)
6
-57 Electrical System
6
-61 Removing the Rear Seat Cushion
6
-66 Replacement Bulbs
6
-66 Capacities and Specifications
6
-67 Air Conditioning Refrigerants
6
-67 Normal Maintenance Replacement Parts

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CAUTION: (Continued)

Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
Use premium unleaded gasoline rated at 91 octane or
higher. It is recommended that the gasoline meet
specifications which have been developed by the
American Automobile Manufacturers Association
(AAMA) and endorsed by the Canadian Motor Vehicle
Manufacturers Association for better vehicle performance
and engine protection. Gasolines meeting the AAMA
specification could provide improved driveability and
emission control system performance compared to othergasolines. For more information, write to: American
Automobile Manufacturer's Association, 7430 Second
Ave, Suite 300, Detroit MI 48202.
Be sure the posted octane for premium is at least 91. If
the octane is less than 91, you may get a heavy knocking
noise when you drive. (In an emergency, you may be
able to use a lower octane
-- as low as 87 -- if heavy
knocking does not occur.) If you're using 91 or higher
octane unleaded gasoline and you hear heavy knocking,
your engine needs service.
If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
label), it is designed to operate on fuels that meet
California specifications. If such fuels are not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specifications, but emission control system
performance may be affected. The malfunction indicator
lamp on your instrument panel may turn on and/or your
vehicle may fail a smog
-check test. (See ªMalfunction
Indicator Lampº in the Index.) If this occurs, return to
your authorized Buick dealer for diagnosis to determine
the cause of failure. In the event it is determined that the
cause of the condition is the type of fuels used, repairs
may not be covered by your warranty.

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Some gasolines that are not reformulated for low
emissions may contain an octane
-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask your service station operator whether or not
the fuel contains MMT. General Motors does not
recommend the use of such gasolines. If fuels containing
MMT are used, spark plug life may be reduced and your
emission control system performance may be affected.
The malfunction indicator lamp on your instrument
panel may turn on. If this occurs, return to your
authorized Buick dealer for service.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent deposits from forming in your engine and fuel
system, allowing your emission control system to
function properly. Therefore, you should not have to add
anything to the fuel. In addition, 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 specifications described earlier.NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don't use it. It can corrode
metal parts in your fuel system and also damage
plastic and rubber parts. That damage wouldn't
be covered under your warranty.
Fuels in Foreign Countries
If you plan on driving in another country outside the United
States or Canada, the proper fuel may be hard to find. Never
use leaded gasoline or any other fuel not recommended in the
previous text on fuel. Costly repairs caused by use of
improper fuel wouldn't be covered by your warranty.
To check on fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you'll be driving.
You can also write us at the following address for
advice. Just tell us where you're going and give your
Vehicle Identification Number (VIN).
General Motors Overseas Distribution Corporation
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7

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Filling a Portable Fuel Container
CAUTION:
Never fill a portable fuel container while it is in
your vehicle. Static electricity discharge from the
container can ignite the gasoline vapor. You can
be badly burned and your vehicle damaged if this
occurs. To help avoid injury to you and others:

Dispense gasoline only into
approved containers.

Do not fill a container while it is inside a
vehicle, in a vehicle's trunk, pickup bed or
on any surface other than the ground.

Bring the fill nozzle in contact with the
inside of the fill opening before operating
the nozzle. Contact should be maintained
until the filling is complete.

Don't smoke while pumping gasoline.
Checking Things Under the Hood
CAUTION:
An electric fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
CAUTION:
Things that burn can get on hot engine parts and
start a fire. These include liquids like gasoline,
oil, coolant, brake fluid, windshield washer and
other fluids, and plastic or rubber. You or others
could be burned. Be careful not to drop or spill
things that will burn onto a hot engine.

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Your vehicle has a 3800 Supercharged V6 engine. The
supercharger is a device designed to pump more air into
the engine than it would normally use. This air, mixed
with fuel, creates increased engine power. Since the
supercharger is a pump and is driven from an engine
accessory drive belt, increased pressure is available at
all driving conditions.
The Powertrain Control Module (PCM) works with a
vacuum control to regulate the increased pressure
required during specific driving conditions. When this
increased pressure or boost is not desired, such as during
idling and light throttle cruising, the excess air that the
supercharger is pumping is routed through a bypass. All
of these controls working together provide high
performance, character and fuel efficiency in the 3800
V6 Supercharged engine.
Engine Oil
If the CHECK OIL LEVEL
light on the instrument
panel comes on, it means
you need to check your
engine oil level right away.For more information, see ªCheck Oil Level Lightº in
the Index. You should check your engine oil level
regularly; this is an added reminder.
It's a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil must
be warm and the vehicle must be on level ground.
The engine oil dipstick is a
round, yellow loop located
directly behind the
engine fan.
Turn off the engine and give
the oil several minutes to
drain back into the oil pan.
If you don't, the oil dipstick
might not show the
actual level.

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6-12 Checking Engine Oil
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
When to Add Engine Oil
If the oil is at or below the ADD mark, then you'll need
to add at least one quart of oil. But you must use the
right kind. This part explains what kind of oil to use. For
crankcase capacity, see ªCapacities and Specificationsº
in the Index.
NOTICE:
Don't add too much oil. If your engine has so
much oil that the oil level gets above the
cross
-hatched area that shows the proper
operating range, your engine could be damaged.
Add engine oil at the engine oil fill cap next to the
oil dipstick.
Be sure to fill it enough to put the level somewhere in
the proper operating range. Push the dipstick all the way
back in when you're through.

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Supercharger Oil
Unless you are technically
qualified and have the
proper tools, you should let
your dealer or a qualified
service center perform this
maintenance.
When to Check
Check oil level every 30,000 miles (50 000 km) or every
36 months, whichever occurs first.
What Kind of Oil to Use
See ªRecommended Fluids and Lubricantsº in the Index
and use only the recommended oil.
How to Check and Add Oil
Check oil only when the engine is cold. Allow the
engine to cool two to three hours after running.
CAUTION:
If you remove the supercharger oil fill plug while
the engine is hot, pressure may cause hot oil to
blow out of the oil fill hole. You may be burned.
Do not remove the plug until the engine cools.
1. Clean the area around the oil fill plug before
removing it.
2. Remove the oil fill plug using a 3/16 inch
Allen wrench.
3. The oil level is correct when it just reaches the
bottom of the threads of the inspection hole.
4. Replace the oil plug with the O
-ring in place. Torque
to 88 lb
-in (10 N´m).