2005 BUICK LACROSSE engine

Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM parts
and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or emit
these chemicals.
5-3

Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airow around it. This may cause wind
noise and affect windshield washer performance. Check
with your dealer before adding equipment to the
outside of your vehicle.
Fuel
The 8th digit of your vehicle identication number (VIN)
shows the code letter or number that identies your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identication Number
(VIN) on page 5-86.
Gasoline Octane
If your vehicle has the 3800 V6 engine, use regular
unleaded gasoline with a posted octane of 87 or higher.
If the octane is less than 87, you may get 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 might damage your engine. A
little pinging noise when you accelerate or drive
uphill is considered normal. This does not indicate a
problem exists or that a higher-octane fuel is necessary.
If you are using 87 octane or higher-octane fuel and
hear heavy knocking, your engine needs service.
If your vehicle has the 3.6L V6 engine, use regular
unleaded gasoline with a posted octane of 87 or higher.
However, for best performance and for trailer towing,
you may wish to use middle grade or premium unleaded
gasoline. If the octane is less than 87, you may get 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 might damage your engine.
5-5

Gasoline Specications
It is recommended that gasoline meet specications
which were developed by automobile manufacturers
around the world and contained in the World-Wide Fuel
Charter which is available from the Alliance of
Automobile Manufacturers at
www.autoalliance.org/fuel_charter.htm. Gasoline
meeting these specications could provide improved
driveability and emission control system performance
compared to other gasoline.
California Fuel
If your vehicle is certied to meet California Emission
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, your
vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance may be affected. The malfunction indicator
lamp may turn on and your vehicle may fail asmog-check test. SeeMalfunction Indicator Lamp on
page 3-39. 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.
Additives
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. In
most cases, you should not have to add anything to your
fuel. However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. General Motors
recommends that you buy gasolines that are advertised
to help keep fuel injectors and intake valves clean. If your
vehicle experiences problems due to dirty injectors or
valves, try a different brand of gasoline. Also, your GM
dealer has additives that will help correct and prevent
most deposit-related problems.
5-6

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 your
engine when you are refueling. Do not smoke
if you are near fuel or refueling your vehicle.
Keep sparks, ames and smoking materials
away from fuel. Do not leave the fuel pump
unattended when refueling your vehicle — this
is against the law in some places. 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’s side of the vehicle.
To remove the fuel cap, turn it slowly to the left
(counterclockwise). The fuel cap has a spring in it;
if the cap is released too soon, it will spring back to
the right.
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
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
Dispense gasoline 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 gasoline.
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, here is what you will see:
5-12

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. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-28.
E. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-90.
F. Engine Coolant Surge Tank. SeeCooling System on
page 5-26.
G. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-24.
H. Power Steering Fluid Reservoir (Below Generator).
SeePower Steering Fluid on page 5-33.I. Electric Engine Cooling Fans. SeeCooling System
on page 5-26.
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 5-21.
M. Engine Coolant Bleed Valve. See “How to Add
Coolant to the Radiator” underCooling System on
page 5-26.
N. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-35.
O. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-19.
5-13

When you open the hood on the 3.6L V6 engine, here is what you will see:
5-14