engine BUICK REGAL 2015 Repair Manual

Black plate (26,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-26 Driving and Operating
Running the Vehicle
While Parked
It is better not to park with the
engine running.
If the vehicle is left with the engine
running, follow the proper steps to
be sure the vehicle will not move.
SeeShifting Into Park on page 9-23
and Engine Exhaust on page 9-25.
If the vehicle has a manual
transmission, see Parking on
page 9-24.
Automatic
Transmission
The mode or selected gear is shown
in the instrument cluster.
P (Park): This position locks the
drive wheels. It is the best position
to use when starting the engine
because the vehicle cannot move
easily.
{Warning
It is 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.
Do not leave the vehicle when the
engine is running. 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,
always set the parking brake and
move the shift lever to P (Park).
See Shifting Into Park on
page 9-23.
Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control
system. The regular brake must be
fully applied first and then the shift
lever button pressed before shifting
from P (Park) when the ignition key

Black plate (27,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-27
is in ON/RUN. If you cannot shift out
of P (Park), ease pressure on the
shift lever, then push the shift lever
all the way into P (Park) as you
maintain brake application. Then
press the shift lever button and
move the shift lever into another
gear. SeeShifting out of Park
(Automatic Transmission) on
page 9-24.
Without the brake pedal applied, the
control indicator will be on.
If the shift lever is not in P (Park)
when the ignition is turned to OFF,
the control indicator and P will flash. R (Reverse):
Use this gear to
back up.
{Caution
Shifting to R (Reverse) while the
vehicle is moving forward could
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Shift to
R (Reverse) only after the vehicle
is stopped.
To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission, see If
the Vehicle Is Stuck on page 9-9.
N (Neutral): In this position, the
engine does not connect with the
wheels. To restart the engine when
the vehicle is already moving, use
N (Neutral) only with the brake pedal
applied.
{Warning
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed.
{Caution
Shifting out of P (Park) or
N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.

Black plate (28,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-28 Driving and Operating
D (Drive):This position is for
normal driving. It provides the best
fuel economy. If more power is
needed for passing, and the
vehicle is:
.Going less than 56 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 56 km/h (35 mph) or
more, push the accelerator all
the way down.
{Caution
If the vehicle accelerates slowly,
or does not shift gears, the
transmission could be damaged.
Have the vehicle serviced
right away.
Manual Mode
Driver Shift Control (DSC)
{Caution
Driving with the engine at a high
rpm without upshifting while using
Driver Shift Control (DSC), could
damage the vehicle. Always
upshift when necessary while
using DSC.
DSC allows you to shift an
automatic transmission similar to a
manual transmission. To use the
DSC feature:
1. Move the shift lever to the left from D (Drive) into the side gate
marked with (+) and (−).
2. Press the shift lever forward to upshift or rearward to downshift.
While using the DSC feature, the
vehicle will have firmer, quicker
shifting. You can use this for sport
driving or when climbing or
descending hills, to stay in gear
longer, or to downshift for more
power or engine braking.
The transmission will only allow you
to shift into gears appropriate for the
vehicle speed and engine
revolutions per minute (rpm). The
transmission will not automatically
shift to the next lower gear if the
engine rpm is too high, nor to the
next higher gear when the maximum
engine rpm is reached.

Black plate (29,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-29
While in the DSC mode, the
transmission will automatically
downshift when the vehicle comes
to a stop. This will allow for more
power during take-off.
When accelerating the vehicle from
a stop in snowy and icy conditions,
you may want to shift into second
gear. A higher gear allows the
vehicle to gain more traction on
slippery surfaces. Vehicles with a
turbocharged engine may also start
in third gear.Manual Transmission
This is the shift pattern for the
6-speed manual transmission.
To operate the transmission:
{Caution
Do not rest your hand on the shift
lever while driving. The pressure
could cause premature wear in
the transmission. The repairs
would not be covered by the
vehicle warranty.
{Caution
Do not rest your foot on the clutch
pedal while driving or while
stopped. The pressure can cause
premature wear in the clutch. The
repairs would not be covered by
the vehicle warranty.
1 (First): Press the clutch pedal
fully to the pedal stop and shift into
1 (First). Then slowly let up on the
clutch pedal as you press the
accelerator pedal.
If you come to a complete stop and
it is hard to shift into 1 (First), put
the shift lever in Neutral and let up
on the clutch. Press the clutch pedal
back down. Then shift into 1 (First).
2 (Second): Press the clutch pedal
as you let up on the accelerator
pedal and shift into 2 (Second).
Then, slowly let up on the clutch
pedal as you press the accelerator
pedal.

Black plate (30,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-30 Driving and Operating
3 (Third), 4 (Fourth), 5 (Fifth), and
6 (Sixth):Shift into 3 (Third),
4 (Fourth), 5 (Fifth), and 6 (Sixth) the
same way you do for 2 (Second).
Slowly let up on the clutch pedal as
you press the accelerator pedal. For
the best fuel economy, use 6 (Sixth)
gear whenever vehicle speed and
driving conditions allow.
The vehicle may have an up-shift
light in the instrument cluster. See
Up-Shift Light on page 5-25.
{Warning
If you skip a gear when
downshifting, you could lose
control of the vehicle. You could
injure yourself or others. Do not
shift down more than one gear at
a time when downshifting.
{Caution
Do not rest your foot on the clutch
pedal while driving or while
stopped. The pressure can cause
premature wear in the clutch. The
repairs would not be covered by
the vehicle warranty.
To stop, let up on the accelerator
pedal and press the brake pedal.
Just before the vehicle stops, press
the clutch pedal and the brake
pedal, and shift to Neutral.
Neutral: Use this position when
you start or idle the engine. The
shift lever is in Neutral when it is
centered in the shift pattern, not in
any gear.
R (Reverse): To back up, with the
vehicle at a complete stop, press
down the clutch pedal. Then pull up
on the button on the shift lever, and
shift into R (Reverse). Let up on the
clutch pedal slowly while pressing
the accelerator pedal. If R (Reverse) gear does not engage, shift the
transmission to Neutral, release the
clutch pedal, and press it back
down. Repeat the gear selection.
{Caution
Shifting to R (Reverse) while the
vehicle is moving forward could
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Shift to
R (Reverse) only after the vehicle
is stopped.
Use R (Reverse) along with the
parking brake to park the vehicle.
When operating, press the clutch
pedal down completely. Do not use
the pedal as a foot rest.

Black plate (32,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-32 Driving and Operating
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies
ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Parking Brake
The Electric Parking Brake (EPB)
switch is on the center console. The
EPB can always be activated, even
if the ignition is off. To prevent
draining the battery, avoid repeated
cycles of the EPB when the engine
is not running.The system has a red parking brake
status light and an amber parking
brake warning light. See
Electric
Parking Brake Light on page 5-24
and Service Electric Parking Brake
Light on page 5-24. There are also
parking brake-related Driver
Information Center (DIC) messages.
See Brake System Messages on
page 5-39. In case of insufficient
electrical power, the EPB cannot be
applied or released.
Before leaving the vehicle, check
the red parking brake status light to
ensure that the parking brake is
applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a complete stop.
2. Lift up the EPB switch momentarily.

Black plate (35,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-35
Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak®, an
electronic stability control system.
These systems help limit wheel slip
and assist the driver in maintaining
control, especially on slippery road
conditions.
TCS activates if it senses that any
of the drive wheels are spinning or
beginning to lose traction. When this
happens, TCS applies the brakes to
the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak selectively applies
braking pressure to any one of the vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
traction control or StabiliTrak begins
to limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See
If the Vehicle Is Stuck on
page 9-9 and“Turning the Systems
Off and On” later in this section.
The indicator light for both systems
is in the instrument cluster. This
light will:
.Flash when TCS is limiting
wheel spin.
.Flash when StabiliTrak is
activated.
.Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.

Black plate (36,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-36 Driving and Operating
Ifdcomes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait 15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes on
and stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.
Turning the Systems Off
and On
To turn the system off, press the
TCS/StabiliTrak button on the center
stack.
{Caution
Do not repeatedly brake or
accelerate heavily when TCS is
off. The vehicle driveline could be
damaged.
To turn off only TCS, press and
release the TCS/StabiliTrak
g
button. The traction off lighti
displays in the instrument cluster.
The appropriate message displays
in the DIC. See Ride Control
System Messages on page 5-45.
To turn TCS on again, press and
release the TCS/StabiliTrak
g
button. The traction off lighti
displayed in the instrument cluster
will turn off.
If TCS is limiting wheel spin when
the TCS/StabiliTrak button is
pressed, the system will not turn off
until the wheels stop spinning. To turn off both TCS and
StabiliTrak, press and hold the TCS/
StabiliTrak
gbutton until the
traction off light
iand StabiliTrak
OFF Light
gcome on and stay on
in the instrument cluster. The
appropriate message displays in the
DIC. See Ride Control System
Messages on page 5-45.
To turn TCS and StabiliTrak on
again, press and release the TCS/
StabiliTrak button. The traction off
light
iand StabiliTrak OFF Lightg
in the instrument cluster turn off.
Adding accessories can affect the
vehicle performance. See
Accessories and Modifications on
page 10-3.

Black plate (59,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-59
When LDW is on,@is green if
LDW is available to warn of a lane
departure. If the vehicle crosses a
detected lane marking without using
the turn signal in that direction,
@
changes to amber and flashes.
Additionally, there will be three
beeps on the right or left, depending
on the lane departure direction.
When the System Does Not
Seem to Work Properly
The system may not detect lanes as
well when there are:
.Close vehicles ahead.
.Sudden lighting changes, such
as when driving through tunnels.
.Banked roads.
If the LDW system is not functioning
properly when lane markings are
clearly visible, cleaning the
windshield may help.
LDW alerts may occur due to tar
marks, shadows, cracks in the road,
temporary or construction lane
markings, or other road
imperfections. This is normal system
operation; the vehicle does not need
service. Turn LDW off if these
conditions continue.
Fuel
Use of the recommended fuel is an
important part of the proper
maintenance of this vehicle. When
driving in the U.S. and Canada, to
help keep the engine clean and
maintain optimum vehicle
performance, we recommend using
TOP TIER Detergent Gasolines.
See www.toptiergas.com for a list of
TOP TIER Detergent Gasolines.

Black plate (60,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-60 Driving and Operating
If the vehicle has a yellow fuel cap,
E85 or FlexFuel can be used in the
vehicle. SeeE85 or FlexFuel on
page 9-61.
If the vehicle has a 2.4L L4 engine,
use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 or
higher. Do not use gasoline with an
octane rating below 87, as it may
cause engine damage and will lower
fuel economy.
If the vehicle has the 2.0L L4 turbo
engine, use premium unleaded
gasoline meeting ASTM
specification D4814 with a posted
octane rating of 91 or higher.
Regular unleaded gasoline rated at
87 octane or higher can be used,
but acceleration and fuel economy
will be reduced, and an audible
knocking noise may be heard. If this
occurs, use a gasoline rated at
91 octane or higher as soon as
possible. Otherwise, the engine
could be damaged. If heavy knocking is heard when using
gasoline with a 91 octane rating or
higher, the engine needs service.
Use of Seasonal Fuels
Use summer and winter fuels in the
appropriate season. The fuels
industry automatically modifies the
fuel for the appropriate season.
If fuel is left in the vehicle tank for
long periods of time, driving or
starting could be affected. Drive the
vehicle until the fuel is at one-half
tank or less, then refuel with the
current seasonal fuel.
Prohibited Fuels
Gasolines containing oxygenates
such as ethers and ethanol, as well
as reformulated gasolines, are
available in some cities. If these
gasolines comply with the
previously described specification,
then they are acceptable to use.
However, E85 (85% ethanol) and
other fuels containing more than
15% ethanol must be used only in
FlexFuel vehicles.{Caution
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, mainly high octane
racing gasolines, can contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). Do not use
gasolines and/or fuel additives with
MMT as they can reduce spark plug
life and affect emission control
system performance. The
malfunction indicator lamp may turn
on. If this occurs, see your dealer
for service.