2009 BUICK LACROSSE engine

If doing some of your own service work, use the proper
service manual. It tells you much more about how to
service the vehicle than this manual can. To order
the proper service manual, seeService Publications
Ordering Information on page 7-16.
This vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-66.
Keep a record with all parts receipts and list the
mileage and the date of any service work performed.
SeeMaintenance Record on page 6-15.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect the
airow around it. This can cause wind noise and can
affect fuel economy and windshield washer performance.
Check with your dealer/retailer before adding equipment
to the outside of the vehicle.
Fuel
Use of the recommended fuel is an important part
of the proper maintenance of this vehicle. To help
keep the engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-98.
5-5

Gasoline Octane
If the vehicle has the 3.8L V6 engine (VIN Code 2),
use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you might notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this occurs,
use a gasoline rated at 87 octane or higher as soon as
possible. If you are using gasoline rated at 87 octane or
higher and you hear heavy knocking, the engine needs
service.
If the vehicle has the 5.3L V8 engine (VIN Code C),
use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular unleaded
gasoline rated at 87 octane or higher, but the vehicle’s
acceleration could be slightly reduced, and you might
notice a slight audible knocking noise, commonly referred
to as spark knock. If the octane is less than 87, you might
notice a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you could damage the
engine. If you are using gasoline rated at 87 octane or
higher and you hear heavy knocking, the engine needs
service.
Gasoline Specications
At a minimum, gasoline should meet ASTM specication
D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in
Canada. Some gasolines contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend against the use of
gasolines containing MMT. SeeAdditives on page 5-7
for additional information.
California Fuel
If the vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specications. See the underhood emission
control label. If this fuel is not available in states adopting
California emissions standards, the vehicle will operate
satisfactorily on fuels meeting federal specications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and the
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-40. If this occurs, return to your
authorized dealer/retailer for diagnosis. If it is determined
that the condition is caused by the type of fuel used,
repairs might not be covered by the vehicle warranty.
5-6

Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, you should not have to add anything to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if the vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS
is the only gasoline additive recommended by General
Motors.
Also, your dealer/retailer has additives that will help
correct and prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend that you use these gasolines,
if they comply with the specications described earlier.
However, E85 (85% ethanol) and other fuels containing
more than 10% ethanol must not be used in vehicles that
were not designed for those fuels.Notice:This vehicle was not designed for fuel
that contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance
of the emission control system could be affected.
The malfunction indicator lamp might turn on. If this
occurs, return to your dealer/retailer for service.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by the vehicle warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in
the country where you will be driving.
5-7

Filling the Tank
{CAUTION:
Fuel vapor burns violently and a fuel re can
cause bad injuries. To help avoid injuries to you
and others, read and follow all the instructions on
the pump island. Turn off the engine when you are
refueling. Do not smoke if you are near fuel or
refueling the vehicle. Do not use cellular phones.
Keep sparks, ames, and smoking materials away
from fuel. Do not leave the fuel pump unattended
when refueling the vehicle. This is against the law
in some places. Do not re-enter the vehicle while
pumping fuel. Keep children away from the fuel
pump; never let children pump fuel.The tethered fuel cap is located behind a hinged fuel
door on the driver side of the vehicle.
To remove the fuel cap, turn it slowly counterclockwise.
While refueling, hang the tethered fuel cap from the
hook on the fuel door.
5-8

Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
the vehicle. Static electricity discharge from the
container can ignite the fuel vapor. You can be
badly burned and the vehicle damaged if this
occurs. To help avoid injury to you and others:
Dispense fuel only into approved containers.
Do not ll 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 ll nozzle in contact with the inside
of the ll opening before operating the nozzle.
Contact should be maintained until the lling
is complete.
Do not smoke while pumping fuel.
Do not use a cellular phone while
pumping fuel.
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 re. These include liquids like fuel, oil,
coolant, brake uid, windshield washer and other
uids, 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.
5-10

Engine Compartment Overview
When you open the hood on the 3.8L V6 engine, this is what you will see:
5-12

A. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-35.
B.Battery on page 5-40.
C. Remote Positive (+) Terminal. SeeJump Starting on
page 5-41.
D.Passenger Compartment Air Filter on page 3-29.
E.Underhood Fuse Block on page 5-101.
F. Engine Coolant Recovery Tank. SeeCooling System
on page 5-24.
G.Radiator Pressure Cap on page 5-31.
H. Power Steering Fluid Reservoir (Out of View).
SeePower Steering Fluid on page 5-34.
I. Electric Engine Cooling Fans. SeeCooling System
on page 5-24.J. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
K. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
L. Automatic Transmission Fluid Dipstick.
See “Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-22.
M. Engine Coolant Bleed Valve. See “How to Add
Coolant to the Radiator” underCooling System on
page 5-24.
N. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-37.
O.Engine Air Cleaner/Filter on page 5-20.
5-13

When you open the hood on the 5.3L V8 engine, here is what you will see:
5-14