engine BUICK LESABRE 2003 Repair Manual

If you choose to perform
the engine oil change
service yourself, be sure
the oil you use 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
you engine is American
Petroleum Institute certi®ed
for gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the viscosity chart.
SAE 10W-30 is the viscosity grade recommended for
your vehicle. However, you can use SAE 5W-30 if
it's going to be colder than 60ÉF (16ÉC) before your next
oil change. When it is very cold, colder than 0ÉF
(-18ÉC), you should use an SAE 5W-30 oil. These
numbers on an oil container show its viscosity,
or thickness. Do not use other viscosity grade oils, such
as SAE 10W-40 or SAE 20W-50 under any conditions.
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Notice:Use only engine oil with the American
Petroleum Institute Certi®ed For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
žoil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below-20ÉF (-29ÉC), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil (Vehicles
Without the GM Oil Life System)
If any one of these is true for you, use the short trip/city
maintenance schedule:
·Most trips are less than 5 miles (8 km). This is
particularly important when outside temperatures
are below freezing.
·Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
·You frequently tow a trailer or use a carrier on top
of your vehicle.
·The vehicle is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine oil to
break down sooner. If any one of these is true for your
vehicle, then you need to change your oil and ®lter
every 3,000 miles (5 000 km) or 3 months Ð whichever
occurs ®rst.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and ®lter every
7,500 miles (12 500 km) or 12 months Ð whichever
occurs ®rst. Driving a vehicle with a fully warmed engine
under highway conditions will cause engine oil to
break down slower.
When to Change Engine Oil (Vehicles
with the GM Oil Life System)
If so equipped, your vehicle has a computer system that
lets you know when to change the engine oil and
®lter. 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.
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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
®lter must be changed at least once a year and at
this time the system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the system. 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
The GM Oil Life System calculates when to change
your engine oil and ®lter 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 ®ve seconds. The oil life will change
to 100%.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Don't let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer's
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
®lter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Instead, recycle it by
taking it to a place that collects used oil. If you have a
problem properly disposing of your used oil, ask
your dealer, a service station or a local recycling center
for help.
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Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 5-12for
the location of the engine air cleaner/®lter.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/®lter every 15,000 miles
(25 000 km) and replace every 30,000 miles (50
000 km). If you are driving in dusty/dirty conditions,
inspect the ®lter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/®lter remove the ®lter from the
vehicle and lightly shake the ®lter to release loose
dust and dirt. If the ®lter remains ªcakedº with dirt, a new
®lter is required.To inspect or replace the engine air cleaner/®lter do the
following:
1. Lift the latches on the engine air cleaner/®lter
housing cover.
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2. Remove the air intake hose that is snapped over
the throttle body by pulling the hose upward and
away from the throttle body which is located
near the top of the engine.3. Disconnect the
electrical connector
from the air intake
hose. This will allow
you to lift the rear
portion of the engine
air cleaner/®lter
housing.
4. After detaching the hose from the throttle body, pull
back the entire rear portion of the engine air
cleaner/®lter housing by pulling upward and
rearward.
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5. Inspect or replace the engine air cleaner/®lter.
6. Reinstall the rear section of the engine air
cleaner/®lter housing.
7. Reconnect the electrical connector.
8. Reattach the air intake hose by snapping it back
onto the throttle body.
9. Refasten the latches to the engine air cleaner/®lter
housing cover.
{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 back®res. If it isn't there
and the engine back®res, you could be burned.
Don't 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 back®re 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're driving.
5-20

Automatic Transaxle Fluid
When to Check and Change
A good time to check your 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 90ÉF (32ÉC) or higher.
·In hilly or mountainous terrain.
·When doing frequent trailer towing.
·Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the ¯uid and ®lter at 100,000 miles
(166 000 km).
See
Part A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little ¯uid can damage
your transaxle. Too much can mean that some of the
¯uid could come out and fall on hot engine or
exhaust system parts, starting a ®re. Too little ¯uid
could cause the transaxle to overheat. Be sure
to get an accurate reading if you check your
transaxle ¯uid.
Wait at least 30 minutes before checking the transaxle
¯uid level if you have been driving:
·When outside temperatures are above 90ÉF (32ÉC).
·At high speed for quite a while.
·In heavy traffic ± especially in hot weather.
·While pulling a trailer.
To get the right reading, the ¯uid should be at normal
operating temperature, which is 180ÉF to 200ÉF
(82ÉC to 93ÉC).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50ÉF
(10ÉC). If it's colder than 50ÉF (10ÉC), you may have to
drive longer.
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Checking the Fluid Level
Prepare your vehicle as follows:
·Park your vehicle on a level place. Keep the engine
running.
·With the parking brake applied, place the shift lever
in PARK (P).
·With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
·Let the engine run at idle for three to ®ve minutes.Then, without shutting off the engine, follow these steps:
The transaxle ¯uid dipstick
top is a round, red loop
and is located next to the
brake master cylinder
behind the engine block.
See
Engine Compartment
Overview on page 5-12
for more information
on location.
1. Pull out the dipstick and wipe it with a clean rag or
paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
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3. Check both sides of the dipstick, and read the
lower level. The ¯uid level must be in the
cross-hatched area.
4. If the ¯uid level is in the acceptable range, push the
dipstick back in all the way.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transaxle ¯uid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-23.
If the ¯uid level is low, add only enough of the proper
¯uid to bring the level into the cross-hatched area on the
dipstick.
1. Pull out the dipstick.
2. Using a long-neck funnel, add enough ¯uid at the
dipstick hole to bring it to the proper level.
It doesn't take much ¯uid, generally less than
one pint (0.5 L).
Don't over®ll.Notice:
We recommend you use only ¯uid labeled
DEXRONž±III, because ¯uid with that label is
made especially for your automatic transaxle.
Damage caused by ¯uid other than DEXRON
ž±III is
not covered by your new vehicle warranty.
3. After adding ¯uid, recheck the ¯uid level as
described under ªHow to Check,º earlier in this
section.
4. When the correct ¯uid level is obtained, push the
dipstick back in all the way.
Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs ®rst, if you add
only DEX-COOL
žextended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, see
Engine Overheating on
page 5-26.
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A 50/50 mixture of clean, drinkable water and
DEX-COOLžcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as they
should.
Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50,000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOLžcoolant which won't damage
aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you wouldn't get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
žcoolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
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