2008 GMC ACADIA engine

Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
break-in. But it will perform better in the long run if
you follow these guidelines:
If you have all-wheel drive, keep your speed at
55 mph (88 km/h) or less for the rst 500 miles
(805 km).
Do not drive at any one constant speed, fast or
slow, for the rst 500 miles (805 km). Do not
make full-throttle starts. Avoid downshifting to
brake or slow the vehicle.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time the new brake
linings are not yet broken in. Hard stops with new
linings can mean premature wear and earlier
replacement. Follow this breaking-in guideline
every time you get new brake linings.
Do not tow a trailer during break-in. SeeTowing a
Trailer on page 4-30for the trailer towing
capabilities of your vehicle and more
information.
Following break-in, engine speed and load can be
gradually increased.
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Ignition Positions
With the key in the ignition,
you can turn it to four
different positions.
In order to shift out of PARK (P), ignition must be in
ON/RUN or ACC/ACCESSORY and the regular brake
pedal must be applied.
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.
A (LOCK/OFF):This is the only position in which you
can remove the key. This position locks the ignition and
transmission. If the steering wheel is locked, move it from
right to left and turn the key to ACC/ACCESSORY. If
none of this works, then your vehicle needs service.B (ACC/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.
C (ON/RUN):This is the position that the switch returns
to after you start your engine and release the key.
The switch stays in ON/RUN when the engine is
running. But even when the engine is not running, you
can use ON/RUN 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
ACC/ACCESSORY or ON/RUN 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/RUN for normal driving.
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Key In the Ignition
Never leave your vehicle with the keys inside, as it is an
easy target for joy riders or thieves. If you leave the key in
the ignition and park your vehicle, a chime will sound
when you open the driver’s door. Always remember to
remove your key from the ignition and take it with you.
This will lock your ignition and transmission. Also, always
remember to lock the doors.
The battery could be drained if you leave the key in the
ignition while your vehicle is parked. You may not be able
to start your vehicle after it has been parked for an
extended period of time.
Retained Accessory Power (RAP)
These vehicle accessories can be used for up to
10 minutes after the ignition key is turned off:
Audio System
Power Windows
Sunroof (if equipped)Power to the windows and sunroof will work up to
10 minutes or until a door is opened.
The radio continues to work for 10 minutes or until the
driver’s door is opened.
For an additional 10 minutes of operation, close all the
doors and turn the key to ON/RUN and then back to
LOCK/OFF.
All these features will work when the key is in the
ON/RUN or ACC/ACCESSORY positions.
Starting the Engine
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.
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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 ACC/ACCESSORY or LOCK/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
let the cranking motor cool down.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:The 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.
2-28

Engine Coolant Heater
The engine coolant heater, if available, can help in cold
weather conditions at or below 0°F (−18°C) for easier
starting and better fuel economy during engine warm-up.
Plug in the coolant heater at least four hours before
starting your vehicle. An internal thermostat in the
plug-end of the cord may exist which will prevent
engine coolant heater operation at temperatures
above 0°F (−18°C).
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.
2-29

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). SeeShifting Into PARK (P) on
page 2-36. If you are pulling a trailer, see
Towing a Trailer on page 4-30.
2-30

Make sure the shift lever is fully in PARK (P) before
starting the engine. Your vehicle has an automatic
transmission shift lock control system. 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 2-37.
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 4-20.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 the 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.
2-31

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.
2-32