engine BUICK LACROSSE 2012 Workshop Manual

Black plate (19,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-19
{WARNING
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY.
The ignition switch can bind in the
LOCK/OFF position with the wheels
turned off center. If this happens,
move the steering wheel from right
to left while turning the key to ACC/
ACCESSORY. If this does not work,
then the vehicle needs service. B (ACC/ACCESSORY):
This
position provides power to some of
the electrical accessories. It unlocks
the ignition. To move the key from
ACC/ACCESSORY to LOCK/OFF,
the shift lever must be in P (Park).
C (ON/RUN): The ignition switch
stays in this position when the
engine is running. This position can
be used to operate the electrical
accessories, including the
ventilation fan and 12‐volt power
outlet, as well as to display some
warning and indicator lights. This
position can also be used for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. The transmission is also
unlocked in this position. The battery could be drained if the
key is left in the ACC/ACCESSORY
or ON/RUN position with the engine
off. The vehicle might not restart if
the battery is allowed to drain for an
extended period of time.
D (START):
This position starts the
engine. When the engine starts,
release the key. The ignition switch
will return to ON/RUN for normal
driving.
A warning tone sounds when the
driver door is opened when the
ignition is still in ACC/ACCESSORY
and the key is in the ignition.

Black plate (20,1)Buick LaCrosse Owner Manual - 2012
9-20 Driving and Operating
Ignition Positions
(Keyless Access)
The vehicle has an electronic
keyless ignition with pushbutton
start.
Pressing the button cycles it through
three modes, ACC/ACCESSORY,
ON/RUN/START, and Stopping the
Engine/OFF.The transmitter must be in the
vehicle for the system to operate.
If the pushbutton start is not
working, the vehicle may be near a
strong radio antenna signal causing
interference to the keyless access
system. See
Remote Keyless Entry
(RKE) System Operation on
page 2‑4 for more information.
To shift out of P (Park), the vehicle
must be in ACC/ACCESSORY or
ON/RUN and the brake pedal must
be applied.
Stopping the Engine/OFF (No LED
Lights): When the vehicle is
stopped, press the engine START/
STOP button once to turn the
engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) on page 9‑27 for more
information. If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display the
message SHIFT TO PARK in the
Driver Information Center (DIC).
See
Transmission Messages on
page 5‑42 for more information.
When the vehicle is shifted into
P (Park), the ignition system will
switch to OFF.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.

Black plate (21,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-21
2. Shift the vehicle to N (Neutral).This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to a
safe location.
3. Come to a complete stop, shift to P (Park), and turn the ignition
to LOCK/OFF. On vehicles with
an automatic transmission, the
shift lever must be in P (Park) to
turn the ignition switch to the
LOCK/OFF position.
4. Set the parking brake. See Parking Brake on page 9‑36.
{WARNING
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency. If the vehicle cannot be pulled over,
and must be shut off while driving,
switch the ignition to ACC/
ACCESSORY.
ACC/ACCESSORY (Amber LED
Light):
This mode allows you to
use some electrical accessories
when the engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to OFF after
five minutes to prevent battery
rundown.
ON/RUN/START (Green LED
Light): This mode is for driving and
starting. With the ignition off, and
the brake pedal applied, pressing
the button once will place the
ignition system in ON/RUN/START.
Once engine cranking begins,
release the button. Engine cranking
will continue until the engine starts. See
Starting the Engine on
page 9‑22 for more information. The
ignition will then remain in ON/RUN.
Service Only Mode
This power mode is available for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. With the vehicle off, and
the brake pedal not applied,
pressing and holding the button for
more than five seconds will place
the vehicle in Service Only Mode.
The instruments and audio systems
will operate as they do in ON/RUN,
but the vehicle will not be able to be
driven. The engine will not start in
Service Only Mode. Push the button
again to turn the vehicle off.

Black plate (22,1)Buick LaCrosse Owner Manual - 2012
9-22 Driving and Operating
Starting the Engine
Move the shift lever to P (Park) or
N (Neutral). The engine will not start
in any other position. To restart the
engine when the vehicle is already
moving, use N (Neutral) only.
Notice:Do not try to shift to
P (Park) if the vehicle is moving.
If you do, you could damage the
transmission. Shift to P (Park)
only when the vehicle is stopped.
Notice: The engine is designed to
work with the electronics in the
vehicle. If you add electrical parts
or accessories, you could change
the way the engine operates.
Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly. Any
resulting damage would not be
covered by the vehicle warranty. Starting Procedure (Key Access)
1. With your foot off the accelerator
pedal, turn the ignition key to
START. When the engine starts,
let go of the ignition.
The idle speed will go down as
your engine gets warm. Do not
race the engine immediately
after starting it. Operate the
engine and transmission gently
to allow the oil to warm up and
lubricate all moving parts.
The vehicle has a
Computer-Controlled Cranking
System. This feature assists in
starting the engine and protects
components. If the ignition key is
turned to the START position,
and then released when the
engine begins cranking, the
engine will continue cranking for
a few seconds or until the
vehicle starts. If the engine does
not start and the key is held in
START for many seconds,
cranking will be stopped after
15 seconds to prevent cranking motor damage. To prevent gear
damage, this system also
prevents cranking if the engine
is already running. Engine
cranking can be stopped by
turning the ignition switch to
ACC/ACCESSORY or
LOCK/OFF.
Notice: Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start after five to 10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the way
to the floor and holding it there
as you hold the key in START,
or press the START button, for
up to a maximum of 15 seconds.
Wait at least 15 seconds

Black plate (23,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-23
between each try, to allow the
cranking motor to cool down.
When the engine starts, let go of
the key or button, and the
accelerator. If the vehicle starts
briefly but then stops again, do
the same thing. This clears the
extra gasoline from the engine.
Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Starting Procedure (Keyless
Access)
1. If the vehicle has the keyless access system, the transmitter
must be in the vehicle. Put your
foot on the brake pedal and
push the START button. When
the engine begins cranking, let
go of the button.
The idle speed will go down as
your engine gets warm. Do not
race the engine immediately
after starting it. Operate the engine and transmission gently
to allow the oil to warm up and
lubricate all moving parts.
If the transmitter is not in the
vehicle or something is
interfering with the transmitter,
the Driver Information Center
(DIC) will display a message.
See
Key and Lock Messages on
page 5‑39 for more information.
If the battery in the Remote
Keyless Entry (RKE) transmitter
needs replacing, the DIC will
display a message. The vehicle
can still be driven. See “Starting
the Vehicle with a Low
Transmitter Battery” inRemote
Keyless Entry (RKE) System
Operation on page 2‑4 for more
information.
The vehicle has a
Computer-Controlled Cranking
System. This feature assists in
starting the engine and protects
components. If the START
button is pressed, and then
released when the engine begins cranking, the engine
will continue cranking for a
few seconds or until the vehicle
starts. If the engine does not
start and the button is pressed
for many seconds, cranking will
be stopped after 15 seconds to
prevent cranking motor damage.
To prevent gear damage, this
system also prevents cranking if
the engine is already running.
Engine cranking can be stopped
by pressing the START button a
second time.
Notice: Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.

Black plate (24,1)Buick LaCrosse Owner Manual - 2012
9-24 Driving and Operating
2. If the engine does not start afterfive to 10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the way
to the floor and holding it there
as you hold the key in START,
or press the START button, for
up to a maximum of 15 seconds.
Wait at least 15 seconds
between each try, to allow the
cranking motor to cool down.
When the engine starts, let go of
the key or button, and the
accelerator. If the vehicle starts
briefly but then stops again, do
the same thing. This clears the
extra gasoline from the engine.
Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.eAssist Automatic Engine
Start/Stop
{WARNING
Exiting the vehicle, without first
shifting into P (Park), may cause
the vehicle to move, you or others
may be injured. Because the
vehicle has the automatic engine
start/stop feature, the vehicle's
engine might seem to be shut off;
however, once the brake pedal is
released, the engine will start up
again.
Shift to P (Park) and turn the
ignition to LOCK/OFF, before
exiting the vehicle.
Vehicles with eAssist have an
automatic engine start/stop feature.
After the engine is started and has
reached operating temperature, the
auto stop feature may cause the
engine to turn off when the brakes
are applied and the vehicle comes
to a complete stop. The vehicle may remain in auto stop for up to
two minutes. When the brake is
released or the accelerator pedal
applied, the engine will start. The
engine will continue to run until the
next auto stop.
AUTO STOP on the tachometer
signifies that the engine is in auto
stop mode. See
Tachometer on
page 5‑12 for more information.
When the vehicle is turned off, the
tachometer will move to OFF. If the
driver door is opened while in auto
stop mode, a chime will sound.
To restart the engine during auto
stop, release the brake pedal or
press the accelerator pedal. The
engine starts immediately. The
vehicle continues to run until the
next stop.
There are several conditions which
may prevent an auto stop or cause
an auto start.

Black plate (25,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-25
The Engine Will Remain
Running When:
.The engine, transmission,
or high voltage battery is not
warmed up yet.
.The outside temperature is less
than−20°C (−4°F).
.The air conditioning or defrost
system need the compressor to
maintain vehicle comfort. See
Dual Automatic Climate Control
System on page 8‑5 for more
information.
.The shift lever is in P (Park),
N (Neutral), R (Reverse),
or M (Manual Mode).
.The high voltage battery pack
charge is low.
.The hood is not fully closed.
.Brake pedal pressure is high.
.If the MIL is on, auto stop may
be prevented. The Engine Will Restart When:
.The brake pedal is released.
.The accelerator pedal is applied.
.Shifting out of D (Drive) to any
other gear.
.If the eco air conditioning button
is selected, the duration of the
auto stop will depend on the
outside temperature. This
economy mode improves fuel
economy by limiting the effects
of the air conditioning. The
warmer it is outside, the shorter
the time before the engine is
restarted to provide cabin
cooling.
.The climate control system is
turned from off to normal air
conditioning or defrost. See
Dual
Automatic Climate Control
System on page 8‑5 for more
information.
.The engine is required to run for
either heater or climate control
performance. See Dual
Automatic Climate Control
System on page 8‑5 for more
information.
.The high voltage battery pack
charge is low and requires
recharging.
.Auto stop time is greater than
two minutes.
.The hood is opened.

Black plate (26,1)Buick LaCrosse Owner Manual - 2012
9-26 Driving and Operating
Engine Heater
The engine coolant heater,
if available, can help in cold weather
conditions at or below−18°C (0°F)
for easier starting and better fuel
economy during engine warm-up.
Plug in the coolant heater at least
four hours before starting the
vehicle. An internal thermostat in
the plug end of the cord will prevent
engine coolant heater operation at
temperatures above −18°C (0°F).
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap the
electrical cord.
3.6L V6 Engine
The electrical cord is located on
the driver side of the engine
compartment, between the
fender and the engine
compartment fuse block on
vehicles with a six cylinder
engine.
2.4L L4 Engine
The electrical cord is located on
the passenger side of the engine
compartment, between the
fender and the air cleaner on
vehicles with a four cylinder
engine.
3. Plug it into a normal, grounded 110-volt AC outlet.

Black plate (27,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-27
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
overheat and cause a fire. You
could be seriously injured. Plug
the cord into a properly grounded
three-prong 110-volt AC outlet.
If the cord will not reach, use a
heavy-duty three-prong extension
cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it
away from moving engine parts.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
These vehicle accessories can be
used for up to 10 minutes after the
engine is turned off:
.Audio System
.Power Windows
.Sunroof (If Equipped)
.Auxiliary Power Outlet
Power to the audio system will
continue to operate for up to
10 minutes or until the driver door is
opened.
Power to the power windows and
sunroof will continue to operate for
up to 10 minutes or until any door is
opened.
All of these features will work when
the ignition is in ON/RUN or ACC/
ACCESSORY.
Shifting Into Park
{WARNING
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle can
roll. If you have left the engine
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are on
fairly level ground, use the steps
that follow.
1. Hold the brake pedal down and set the parking brake.
See Parking Brake on page 9‑36
for more information.
2. Move the shift lever into P (Park) by pushing the lever all the way
toward the front of the vehicle.
3. Turn the ignition off.

Black plate (28,1)Buick LaCrosse Owner Manual - 2012
9-28 Driving and Operating
Leaving the Vehicle with the
Engine Running
{WARNING
It can be dangerous to leave the
vehicle with the engine running.
The vehicle could move suddenly
if the shift lever is not fully in
P (Park) with the parking brake
firmly set. And, if you leave the
vehicle with the engine running, it
could overheat and even catch
fire. You or others could be
injured. Do not leave the vehicle
with the engine running.If you have to leave the vehicle with
the engine running, be sure the
vehicle is in P (Park) and the
parking brake is firmly set before
you leave it. After you have moved
the shift lever into P (Park), hold
down the regular brake pedal. See if
you can move the shift lever away
from P (Park) without first pulling it
toward you. If you can, it means that
the shift lever was not fully locked
into P (Park).
Torque Lock
Torque lock is when the weight of
the vehicle puts too much force on
the parking pawl in the
transmission. This happens when
parking on a hill and shifting the
transmission into P (Park) is not
done properly and then it is difficult
to shift out of P (Park). To prevent
torque lock, set the parking brake
and then shift into P (Park). To find
out how, see "Shifting Into P (Park)"
listed previously.
If torque lock does occur, your
vehicle may need to be pushed
uphill by another vehicle to relieve
the parking pawl pressure, so you
can shift out of P (Park).
If you are towing a trailer and
parking on a hill, see
Driving
Characteristics and Towing Tips on
page 9‑57.