DIC BUICK LESABRE 2002 Repair Manual

6-4 Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers' Association for better
vehicle performance and engine protection. Gasolines
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasolines.
In Canada, look for
the ªAuto Makers'
Choiceº label on
the pump.
Canada Only
California Fuel
If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label),
it is designed to operate on fuels that meet California
specifications. If this fuel is 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 may
turn on (see ªMalfunction Indicator Lampº in the Index)
and your vehicle may fail a smog
-check test. 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.

6-5 Additives
Some gasolines that are not reformulated for low
emissions may contain an octane
-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may be
affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.
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.
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 fuel containing
methanol. 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.

6-7
CAUTION:
If you get gasoline on yourself and then
something ignites it, you could be badly burned.
Gasoline can spray out on you if you open the
fuel cap too quickly. This spray can happen if
your tank is nearly full, and is more likely in hot
weather. Open the fuel cap slowly and wait for
any ªhissº noise to stop. Then unscrew the cap
all the way.
Be careful not to spill gasoline. Clean gasoline from
painted surfaces as soon as possible. See ªCleaning
the Outside of Your Vehicleº in the Index.
When you put the fuel cap back on, turn it to the right
(clockwise) until you hear a clicking sound. Make sure
you fully install the cap. The diagnostic system can
determine if the fuel cap has been left off or improperly
installed. This would allow fuel to evaporate into the
atmosphere. See ªMalfunction Indicator Lampº in
the Index.The GAS CAP LOOSE
-CHECK CAP message will
be displayed on the Driver Information Center (DIC)
(if equipped) if the fuel cap is not properly reinstalled.
NOTICE:
If you need a new fuel cap, be sure to get the
right type. Your dealer can get one for you. If you
get the wrong type, it may not fit properly. This
may cause your malfunction indicator lamp to
light and may damage your fuel tank and
emissions system. See ªMalfunction Indicator
Lampº in the Index.

6-11
Engine Oil
If the ENGINE OIL LOW-
CHECK LEVEL DIC
message appears on the
instrument cluster, it means
you need to check your
engine oil level right away.
For more information,
see ªDIC Warnings and
Messagesº in the Index.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
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
located right behind the
engine fans and in front
of the engine oil filler cap.
The top of the dipstick is
a round yellow loop. See
ªEngine Compartment
Overviewº in the Index
for more information
on location.

6-13 What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identified by
looking for the starburst symbol.
This symbol indicates that the oil has been certified by
the American Petroleum Institute (API). Do not use any
oil which does not carry this starburst symbol.
If you change your own oil,
be sure you use oil that has
the starburst symbol on the
front of the oil container.
If you have your oil
changed for you, be sure
the oil put into your engine
is American Petroleum
Institute certified for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the following chart:

6-15 When to Change Engine Oil (Vehicles With
the GM Oil Life System
Option)
If so equipped, your vehicle has a computer system
that lets you know when to change the engine oil and
filter. 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 ENGINE OIL SOON message
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
filter must be changed at least once a year and at this
time the system must be reset. 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.
How to Reset the Oil Life System (If Equipped)
The GM Oil Life System
calculates when to change
your engine oil and filter based on vehicle use. Anytime
your oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation
occurs where you change your oil prior to a CHANGE
ENGINE OIL SOON message being turned on, reset
the system.
To reset the Oil Life System, do the following:
1. Display the OIL LIFE INDEX on the DIC.
2. Press and hold the RESET button on the DIC
for more than five seconds. The oil life will change
to 100%.

6-19
Passenger Compartment Air Filter
(If Equipped)
If your vehicle has this feature, the outside air entering
the vehicle is routed through a filter. The filter removes
certain particles from the air, including pollen and dust
particles. Reductions in airflow, which may occur more
often in dusty areas, indicate that the filter may need
to be replaced early.
The filter should be replaced as part of the routine
scheduled maintenance. See ªMaintenance Scheduleº
in the Index for more information.
The passenger compartment
air filter is located on the
passenger side at the base
of the windshield and
can be accessed through
a removable panel under
the hood of the vehicle.To check or replace the air filter:
1. With the hood open, unlatch and remove the
access panel.
2. To remove the filter, press on the spring tab on
the side of the filter housing and pull the filter out
of the housing.
3. To install the new filter, press on the spring tab and
insert the filter into the housing. The filter should be
fully inserted into the upper and lower grooves and
locked into place by the spring tab.
4. Reinstall the air filter access panel at the base of
the windshield.

6-26
Radiator Pressure Cap
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure
-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating. Be sure the arrows on the cap
line up with the overflow tube on the radiator
filler neck.
See ªEngine Compartment Overviewº in the Index for
more information on location.
Power Steering Fluid
The power steering fluid
reservoir is located below
the generator and behind
the accessory drive belt
in the rear of the engine
compartment on the
passenger's side of
the vehicle.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there is a leak in the system
or you hear an unusual noise. A fluid loss in this
system could indicate a problem. Have the system
inspected and repaired.

6-31 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 firmly).
CAUTION:
The brake wear warning sound means that soon
your brakes won't 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 first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in the
proper sequence to GM torque specifications.
Brake linings should always be replaced as complete
axle sets.
See ªBrake System Inspectionº in Section 7 of this
manual under Part C ªPeriodic Maintenance Inspections.º
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you apply the brakes, with or without the
vehicle moving, your brakes adjust for wear.

6-35
4. Turn the bulb retainer counterclockwise to remove it
from the bulb assembly. Pull the bulb straight out
from the retainer.
5. Push the new bulb straight into the retainer.
6. Reverse Steps 1 through 3 to reinstall the
headlamp assembly.Headlamp Aiming
Your vehicle has a visual optical headlamp aiming
system equipped with horizontal aim indicators.
The aim has been preset at the factory and should
need no further adjustment. This is true even though
your horizontal aim indicators may not fall exactly on the
ª0º (zero) marks on their scales.