2007 GMC ACADIA engine

Ignition Positions
With the key in the ignition, you can turn it to four
different positions.
A (OFF):This is the only position in which you
can remove the key. This position locks the ignition
and transmission.
Notice:Using a tool to force the key from the
ignition switch could cause damage or
break the key. Use the correct key and turn the
key only with your hand. Make sure the key
is all the way in. If none of this works,
then your vehicle needs service.B (ACCESSORY):This position allows you to use
things like the radio and the windshield wipers
while the engine is off. This position will also allow
you to turn off the engine. Use ACCESSORY if
you must have your vehicle in motion while
the engine is off, for example, if your vehicle is
being pushed or towed.
C (ON):This is the position that the switch
returns to after you start your engine and release
the key. The switch stays in ON when the
engine is running. But even when the engine is
not running, you can use ON to operate your
electrical power accessories, and to display some
instrument panel warning lights.
The battery could be drained if you leave the key
in the ACCESSORY or ON position with the
engine off. You may not be able to start your
vehicle 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 for normal driving.
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Starting the Engine
Place the transmission in the proper gear.
Move your shift lever to PARK (P) or
NEUTRAL (N). Your engine will not start
in any other position – this is a safety feature.
To restart when you are already moving, use
NEUTRAL (N) only.
Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could
damage the transmission. Shift to PARK (P)
only when your vehicle is stopped.
Starting Procedure
1. With your foot off the accelerator pedal, turn
the ignition key to START. When the engine
starts, let go of the key. 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.Your 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 the
ACCESSORY or OFF position.
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 allow
the cranking motor to cool down.
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2. If the engine does not start after 5-10 seconds,
especially in very cold weather (below 0°F or
−18°C), it could be ooded with too much
gasoline. Try pushing the accelerator pedal all
the way to the oor and holding it there as
you hold the key in START 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 and accelerator. If
the vehicle starts briey 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.
Notice:Your engine is designed to work with
the electronics in your vehicle. If you add
electrical parts or accessories, you could
change the way the engine operates. Before
adding electrical equipment, check with
your dealer/retailer. If you do not, your engine
might not perform properly. Any resulting
damage would not be covered by your
vehicle’s warranty.Engine Coolant Heater
Your vehicle may have an engine coolant heater.
In very cold weather, 0°F (−18°C) or colder,
the engine coolant heater can help. You will get
easier starting and better fuel economy during
engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your
vehicle. At temperatures above 32°F (0°C), use of
the coolant heater is not required. Your vehicle
may also have an internal thermostat in the
plug end of the cord. This will prevent operation of
the engine coolant heater when the temperature
is at or above 0°F (−18°C) as noted on the cord.
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To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical
cord. The cord is located on the driver’s
side of the engine compartment, it is routed
around the windshield washer uid reservoir.
3. Plug the cord into a normal, grounded 110-volt
AC outlet.
{CAUTION:
Plugging the cord into an ungrounded
outlet could cause an electrical shock.
Also, the wrong kind of extension cord
could overheat and cause a re. 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. If you do
not, it could be damaged.
How long should you keep the coolant heater
plugged in? The answer depends on the outside
temperature, the kind of oil you have, and
some other things. Instead of trying to list
everything here, we ask that you contact your
dealer/retailer in the area where you will be parking
your vehicle. The dealer/retailer can give you
the best advice for that particular area.
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Automatic Transmission Operation
Your vehicle has an electronic shift position
indicator within the instrument panel cluster.
When using the Electronic Range Select Mode a
number will display next to the L, indicating
the current gear that has been selected.
See Electronic Range Select mode in this section
for more information.
Your automatic transmission has a shift lever
located on the console between the seats.
PARK (P):This position locks your front wheels. It
is the best position to use when you start your
engine because your vehicle cannot move easily.{CAUTION:
It is dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P)
with the parking brake rmly set. Your
vehicle can roll.
Do not leave your vehicle when the engine
is running unless you have to. If you have
left the engine running, the vehicle can
move suddenly. You or others could be
injured. To be sure your vehicle will not
move, even when you are on fairly level
ground, always set your parking brake
and move the shift lever to PARK (P). See
Shifting Into Park (P) on page 135.Ifyou
are pulling a trailer, seeTowing a Trailer
on page 371.
Make sure the shift lever is fully in PARK (P)
before starting the engine. Your vehicle has an
automatic transmission shift lock control system.
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You must fully apply your regular brake rst and
then press the shift lever button before you
can shift from PARK (P) when the ignition key is in
ON. If you cannot shift out of PARK (P), ease
pressure on the shift lever, then push the
shift lever all the way into PARK (P) as you
maintain brake application. Then press the shift
lever button and move the shift lever into another
gear. SeeShifting Out of Park (P) on page 137.
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your
vehicle is moving forward could damage the
transmission. The repairs would not be covered
by your warranty. Shift to REVERSE (R) only
after your vehicle is stopped.
To rock your vehicle back and forth to get out of
snow, ice or sand without damaging your
transmission, seeIf Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow on page 360.
NEUTRAL (N):In this position, your engine does
not connect with the wheels. To restart when
you are already moving, use NEUTRAL (N) only.
Also, use NEUTRAL (N) when your vehicle is
being towed.
{CAUTION:
Shifting into a drive gear while your
engine is running at high speed is
dangerous. Unless your foot is rmly on
the brake pedal, your vehicle could move
very rapidly. You could lose control and
hit people or objects. Do not shift into a
drive gear while your engine is running at
high speed.
Notice:Shifting out of PARK (P) or
NEUTRAL (N) with the engine running at high
speed may damage the transmission. The
repairs would not be covered by your warranty.
Be sure the engine is not running at high
speed when shifting your vehicle.
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DRIVE (D):This position is for normal driving. It
provides the best fuel economy for your vehicle. If
you need more power for passing, and you are:
Going less than 35 mph (56 km/h), push
your accelerator pedal about halfway down.
Going about 35 mph (56 km/h) or more, push
the accelerator all the way down.
Notice:If your vehicle seems to accelerate
slowly or not shift gears when you go faster,
and you continue to drive your vehicle that
way, you could damage the transmission. Have
your vehicle serviced right away. You can
drive in LOW (L) when you are driving less than
35 mph (56 km/h) and DRIVE (D) for higher
speeds until then.
LOW (L):This position gives you access to gear
ranges. This provides more engine braking but
lower fuel economy than DRIVE (D). You can use
it on very steep hills, or in deep snow or mud.
Electronic Range Select Mode
Electronic Range Selector (ERS) mode allows you
to choose the top-gear limit of the vehicle’s
transmission and the vehicle’s speed while driving
down hill or towing a trailer.
To use this feature, do the following:
1. Move the shift lever to LOW (L).
2. Press the plus/minus
button located on the
shift lever, to
increase or decrease
the gear range
available based
upon your current
driving conditions
and needs.
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When you shift from DRIVE (D) to LOW (L), the
transmission will shift to a pre-determined
lower gear range. The highest gear available for
this pre-determined range is displayed next to
the L in the DIC. SeeDriver Information Center
(DIC) on page 232andDIC Operation and
Displays (With DIC Buttons) on page 233orDIC
Operation and Displays (Without DIC Buttons)
on page 239for more information. The number
displayed in the DIC is the highest gear that
the transmission will be allowed to operate in.
However, your vehicle can automatically shift to
lower gears as required by various driving
conditions. This means that all gears below that
number are available. For example, when
FOURTH (4) is shown next to the L, FIRST (1)
through FOURTH (4) gears are automatically
shifted by the vehicle. You cannot shift into
FIFTH (5) until the plus (+) button is used or you
shift back into DRIVE (D) mode.While in LOW (L), the transmission will prevent
shifting to a lower gear range if the engine speed
is too high for the gear range you are trying to
select. You have a brief period of time to slow the
vehicle speed. If vehicle speed is not reduced
within the timeframe allowed, the lower gear range
attempted will not be available. The highest
possible gear that is allowed for that engine speed
will display next to the L in the DIC. Try again
to slow the vehicle speed and press the minus (−)
button to the desired lower gear range.
Automatic Engine Grade braking is not available
when the ERS is active. It is available in
DRIVE (D) for both normal and Tow/Haul mode.
While using the ERS, cruise control and the
tow/haul mode can be used. SeeTow/Haul Mode
on page 133for more information.
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