2005 BUICK LACROSSE check engine

A. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-34.
B. Battery. SeeBattery on page 5-38.
C. Remote Positive (+) Terminal. SeeJump Starting on
page 5-39.
D. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-90.
E. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-28.
F. Engine Coolant Surge Tank. SeeCooling System on
page 5-26.
G. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-33.
H. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-24.
I. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
J. Electric Engine Cooling Fans. SeeCooling System
on page 5-26.
K. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.L. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-21.
M. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-35.
N. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-19.
Engine Oil
Checking Engine Oil
It is 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 handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. 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.
5-15

If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), 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
Do not add anything to your oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all you will need for good performance
and engine protection.
Engine Oil Life System
When to Change Engine Oil
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.
When the system has calculated that oil life has
been diminished, it will indicate that an oil change is
necessary. A change engine oil light or, if your vehiclehas the Driver Information Center (DIC), a CHANGE
OIL SOON message will come on. SeeChange Engine
Oil Light on page 3-43orDIC Warnings and Messages
on page 3-53. Change the oil as soon as possible
within the next 600 miles (1 000 km). 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, the 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 the oil at 3,000 miles (5 000 km) since the last
oil change. Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil
Life System
The Engine Oil Life System calculates when to change
the engine oil and lter based on vehicle use. Anytime
the oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation
occurs where you change the oil prior to a change
engine oil light or CHANGE OIL SOON message being
turned on, reset the system.
5-18

Automatic Transmission Fluid
It is not necessary to check the transmission uid level.
A transmission uid leak is the only reason for uid
loss. If a leak occurs, take your vehicle to the dealership
service department and have it repaired as soon as
possible.
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 90°F (32°C) 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, the uid and lter do not require changing.
Notice:Use of automatic transmission uid labeled
other than DEXRON
®-III, Approved for the
H-Specication, may damage your vehicle, and the
damages may not be covered by your warranty.
Always use automatic transmission uid labeled
DEXRON
®-III, Approved for the H-Specication.
Engine Coolant
The cooling system in the vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if only
DEX-COOL
®extended life coolant is added.
The following explains the cooling system and how to
add coolant when it is low. If there is a problem
with engine overheating or if coolant needs to be added
to the radiator, seeEngine Overheating on page 5-24.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®engine coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-21

What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®engine coolant which will
not damage aluminum parts. If this coolant mixture is
used, nothing else needs to be added.
{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 would not 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
®coolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.If coolant needs to be added more than four times a
year, have your dealer check the cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant recovery tank
is located in the engine
compartment toward
the rear of the engine on
the passenger’s side of the
vehicle. SeeEngine
Compartment Overview on
page 5-12for more
information on location.
The vehicle must be on a level surface when checking
the coolant level.
When the engine is cold, the coolant level should be at
the cold ll line or a little higher. The cold ll line is
near the bottom of the surge tank and has an arrow
pointing down at it.3.8L V6 engine shown,
3.6L V6 engine similar
5-22

Adding Coolant
If more coolant is needed, add the proper DEX-COOL®
coolant mixture at the coolant recovery tank, but be
careful not to spill it.
If the coolant recovery tank is completely empty, add
coolant to the radiator. SeeEngine Overheating
on page 5-24.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the
radiator. Never turn the radiator pressure
cap — even a little — when the engine and
radiator are hot.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
Occasionally check the coolant level in the radiator. For
information on how to add coolant to the radiator,
seeCooling System on page 5-26.
5-23

When the engine is cold, the coolant level should be at
or above the cold ll line on the coolant recovery
tank. If it is not, there may be a leak at the pressure cap
or in the radiator hoses, heater hoses, radiator, water
pump, or somewhere else in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive
the vehicle.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, the fans should be running.
If the fans are not running, the vehicle needs service.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-26for information on driving to a safe place
in an emergency.
Notice:Using coolant other than DEX-COOL®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-28

8. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.9. By this time, the coolant level inside the radiator
ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the ller neck until the level reaches
the base of the ller neck.
10. Then replace the radiator pressure cap. At any time
during this procedure if coolant begins to ow out of
the ller neck, reinstall the pressure cap. Be sure
the pressure cap is hand-tight and fully seated.
11. Check the coolant in the recovery tank. The level in
the coolant recovery tank should be at the cold ll
line when the engine is cold.
3.8L V6 engine shown, 3.6L V6 engine similar
5-32

Power Steering Fluid
SeeEngine Compartment
Overview on page 5-12for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How to Check Power Steering Fluid
To check the power steering uid, do the following:
1. Turn the key off and let the engine compartment
cool down.
2. Wipe the cap and the top of the reservoir clean.3. Unscrew the cap and wipe the dipstick with a
clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the uid level on
the dipstick.
If your vehicle has the 3.8L V6 engine, the uid level
should be between the ADD and HOT marks when the
engine is cold, and at the HOT mark when the engine
is hot. If the uid is at the ADD mark when the engine is
cold or hot, power steering uid should be added.
If your vehicle has the 3.6L V6 engine, the uid level
should be between the Min and Max marks when
the engine is cold, and at the Max mark when the engine
is hot. If the uid is at the Min mark when the engine
is cold or hot, power steering uid should be added.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-12.
Always use the proper uid. Failure to use the proper
uid can cause leaks and damage hoses and seals.
5-33