BUICK CENTURY 1993 Owners Manual

Selecting the Right Schedule
First you’ll need to decide which of the two schedules is
right for your vehicle. Here is how to decide which
schedule to follow:
Schedule I
Is any one of these true for your vehicle?
Most trips are less than 4 miles (6 km).
Most trips are less than 10 miles (16 km) when outside
temperatures are below freezing.
The engine is at low speed most of the time (as in
door-to-door delivery, or
in stop-and-go traffic).
You operate your vehicle in dusty areas.
You tow a trailer.
If any one (or more) of these is true for your driving,
follow Schedule
I.
Schedule 11
Follow Schedule II only if none of the above conditions
is true.
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Schedule I
Follow Schedule I if your vehicle is
MAINLY driven under one or more
of the following conditions:
When most trips are less than 4 miles
When most trips are less than
10 miles (16 km) and outside
temperatures remain below freezing.
When most trips include extended
idling and/or frequent low-speed
operation, as
in stop-and-go’ traffic.
(6 km).
When towing a trailer.
When operating in dusty areas.
Schedule I should also be followed if
the vehicle
is used for delivery
service, p?lice,
taxi or other
commercial applications.
* An Emission Control Service.
z2T The U.S. Environmental Protection Agency
has.determined that the failure to perform this
maintenance item will not nullify the emission
wamty
or limit recall liability prior to the
completion of vehicle useful life. General
Motors, however, urges that all recommended
maintenance services
be performed at the
indicated intervals and the maintenance be
recorded in “Section E: Maintenance Record.”
ITEM
NO.
TO BE SERVICED WHEN TO PERFORM
See “Explanation of Scheduled Maintenance Miles (kilometers) or Months
Services” following Schedules
I and D[. (whichever occurs first).
2 I Chassis Lubrication I Every other oil change.
Tire
and Wheel Rotation and Inspection At 6,000 Miles (10 000 km) and every 15,000
Miles (25 000 km) or as necessary. I
61
Cooling System Service* Every 30,000 Miles (50 O00 km) or 24
Months. I
8 I Spark
Plug Replacement* I Every 30,000 Miles (50 000 km). I
EGR System Inspection** Every 30,000 miles (50 OOO km)
(2.2L LA Code 4 engine only)
12 I Fuel Tank, Cap and Lines Inspection** I Every 30,000 Miles (50 OOO km). I
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The services shown in this schedule up to 48,OOO miles (SO 000 km) are to be
performed after 48,000 miles at the same intervals.
MILES (000)
3 16 19 I12 115 I18 121 124 I27 130 133 136 139 142 145 148 ~
KILOMETERS (000)
I I I I I I I I I I I 1 I I 0
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Schedule 11
Follow Schedule II ONLY if none of
the driving conditions specified in Schedule
I apply.
*An Emission Control Service.
I% The U.S. Environmental Protection Agency
has determined that the failure
to perform this
maintenance item will not nullify the
emission warranty
or limit recall liability
prior to the completion of vehicle useful life.
General
Motors, however, urges that all
recommended maintenance services be
performed at the indicated intervals
and the
maintenance be recorded in “Section E:
Maintenance Record.”
TO BE SERVICED ITEM
No’ See “Explanation of Scheduled Maintenance
Services” following Schedules
I and II.
WHEN TO PERFORM
Miles (kilometers) or Months
(whichever
occurs first).
4l
Tire and Wheel Rotation and Inspection
Cooling
System Service* Every 30,000 Miles (50 OOO km) or 24
Every 30,000 Miles (50 000 km).
lo I
Every 30,000 Miles (50 OOO km)
12 I Fuel Tank, Cap and Lines Inspection** I Every 30,000 Miles (50 000 km).
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The services shown in this schedule up to 45,000 miles (75 000 km) are to be
performed after 45,000 miles at the same intervals.
MILES (000)
7.5 15 I 22.5 1 30 I 37.5 I 45
KILOMETERS (000)
12.5 I 25 I 37.5 I 50 1. 62.5 I 75
I 0 I 0 I 0 I 0 I 0 I 0 I
0
I I
0
I I I I I I I 0
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Explanation of Scheduled Maintenance Services
Below are explanations of the services listed in Schedule
I and Schedule II.
The proper fluids and lubricants to use are listed in
Section
D. Make sure whoever services your vehicle uses
ITEM
NO. SERVICE
1 Engine Oil and Filter Change-Always use
SG Energy Conserving 11 oils of proper viscosity.
The “SG” designation may be shown alone or in
combination with others, such as ‘‘SG/CC:’
“SG/CD” or “SF, SG, CC:’ etc.
To determine the preferred viscosity for your
vehicle’s engine (e.g., SAE
5W-30 or SAE
10W-30), see “Engine Oil” in the Index.
2 Chassis Lubrication-Lubricate the transaxle
shift linkage, parking brake cable guides,
underbody contact points and linkage. If your
vehicle is equipped with grease fittings, lubricate
the suspension and steering linkage. these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the vehicle.
NOTE: To determine your engine’s displacement and
code, see “Engine Identification” in the Index.
ITEM
NO. SERVICE
3 Throttle Body Mounting Bolt Torque (3300 V6
Code N Engine Only)*-Check the,torque of
the mounting bolts and/or nuts.
4 Tire and Wheel Rotation and Inspection-For
proper wear and maximum tire life, rotate your
tires following the instructions
in this manual.
See “Tires, Inspection & Rotation” in the Index.
Check the tires for uneven wear or damage. If
you see irregular or premature wear, check the
wheel alignment. Check for damaged wheels also.’
*An Emission Control Service.
~2 The U.S. Environmental Protection Agency has determined that the failure to perform this maintenance item will not nullify the.emission warranty
or limit recall liability prior
to the completion of vehicle useful life. General Motors, however, urges that all recommended maintenance services be
performed at the indicated intervals and the maintenance be recorded in “Section E: Maintenance Record.”
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ITEM
NO. SERVICE
5 Engine Accessory Drive Belt Inspection-
* Inspect the belt for cracks, fraying, wear and
proper tension. Replace as needed.
6 Cooling System Service*-Drain, flush and
refill the system with new or approved recycled
coolant conforming to
GM Specification 1825M.
Keep coolant at the proper mixture as specified. See “Engine Coolant” in the Index. This
provides proper freeze protection, corrosion inhibitor level and engine operating temperature.
Inspect hoses and replace if they are cracked,
swollen or deteriorated. Tighten screw-type hose
clamps. Clean the outside of the radiator and air
conditioning condenser. Wash the pressure cap
and neck.
To help ensure proper operation, we recommend
a pressure test of
both the cooling system and the
pressure cap.
ITEM
NO. SERVICE
7 Transaxle Service-Change both the fluid and
filter every
l5,O00 miles (25 O00 km) if the
vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside tem-
perature regularly reaches
90°F (32OC) or
higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police car or
If you do’not use your vehicle under any of
these conditions, change both the fluid and filter every
100,000 miles (160 0o0 km).
plugs with the proper type. See “Specifications
‘and Capacities” in the Index. delivery service.
8 Spark
Plug Replacement*-Replace spark
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ITEM
NO. SERVICE
9 Spark Plug Wire Inspection**-Inspect for
bums, cracks or other damage. Check the boot
fit at the distributor and at the spark plugs.
Replace wires as needed.
10 Exhaust Gas Recirculation (EGR) System
Inspection (2.2L Code 4 engine only)**-
Conduct the EGR system service as described in
the service manual.
To purchase a service
manual, see “Service Publications” in the Index.
ITEM
NO. SERVICE
12
Air Cleaner Filter Replacement*-Replace
every
30,000 miles (50 OOO km) or more often
under dusty conditions. Ask your dealer for the
proper replacement intervals for your driving conditions.
Fuel %nk, Cap
and Lines Inspection* A-
Inspect fuel tank, cap and lines (including fuel
rails and injection assembly, if equipped) for
damage or leaks. Inspect fuel cap gasket for an
even filler neck imprint or any damage. Replace
parts as needed. Periodic replacement of the fuel
filter is not required.
*An Emission Control Service.
*The
U.S. Environmental Protection Agency has determined that the failure to perform this maintenance item will not nullify the emission warranty
or limit
recall liability prior to the completion of vehicle useful life. General Motors, however, urges that all recommended maintenance services be
performed at the indicated intervals and the maintenance be recorded in “Section E: Maintenance Record.”
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Section B: Owner Checks and Services
Listed below are owner checks and services which should be performed at the intervals specified to help
ensure the safety, dependability and emission control
performance of your vehicle. Be
sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown in
Section
D.
At Each Fuel Fill (It is important for you or a service station attendant to perform these undechd checks at each fuel fill.)
CHECK
I OR SERVICE I WHAT TO DO
Engine Oil Level
Check the engine oil level and add the proper oil if necessar\
y. See “Engine Oil” in the
Index for further details.
Engine Coolant Level Check the engine coolant level in the coolant recovery tank and add \
the proper coolant mix
I if necessary. See “Engine Coolant” in the Index for furth\
er details. I
Windshield Washer Check the windshield washer fluid level in th\
e windshield washer tank and add the proper
Fluid Level
I fluid if necessary. See “Windshield Washer Fluid” in the \
Index for further details. I
At Least Once a Month
CHECK
I OR SERVICE I WHAT TO DO
Tire Inflation Check tire inflation. Make sure they are inflate\
d to the pressures specified on the Tire-
Loading Information label located on the rear edge of the driv\
er’s door. See “Tires”
in the
Index
for further details.
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At Least Once a Year
CHECK
OR SERVICE I WHAT TO DO
I
Key Lock Cylinders I Lubricate the key lock cylinders with the lubricant specified in Section D.
Body Lubrication Lubricate all body door hinges. Also lubricate all hinges and \
latches, including those for the
hood, glove box door and console door. Section
D tells you what to use. I
Starter Switch
When you are doing this check, the vehicle could move suddenly\
. If it does,
1. Before you start, be sure you have enough room around the vehicle.
2. Firmly apply both the parking brake (see “Parking Brake” \
in the Index if necessary) and
NOTE: Do not use the accelerator pedal, and be ready to turn off the engine immediately if
it starts.
3. Try to start the engine in each gear. The starter should work onl\
y in “P” (Park) or “N”
the regular brake.
(Neutral). If the starter works in any other position, your \
vehicle needs service.
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