2009 GMC ENVOY engine

Ignition Positions
The ignition switch has
four different positions.
Press the brake pedal, and turn the ignition to ON/RUN
to shift out of P (Park).
Notice:Using a tool to force the key to turn in the
ignition could cause damage to the switch or
break the key. Use the correct key, make sure it is
all the way in, and turn it only with your hand. If the
key cannot be turned by hand, see your
dealer/retailer.A (LOCK/OFF):This position locks the ignition and
transmission. The key can only be removed in
LOCK/OFF.
The steering can bind 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 doesn’t work, then the vehicle needs service.
B (ACC/ACCESSORY):This is the position in which
you can operate electrical accessories.
C (ON/RUN):This position can be used to operate the
electrical accessories and to display some instrument
panel warning and indicator lights. The switch stays
in this position when the engine is running.
If you leave the key in the ACC/ACCESSORY or
ON/RUN position with the engine off, the battery could
be drained. You may not be able to start the vehicle
if the battery is allowed to drain for an extended period
of time.
D (START):This is the position that starts the engine.
When the engine starts, release the key. The ignition
switch returns to ON/RUN for driving.
A warning tone will sound when the driver door is
opened, the ignition is in ACC/ACCESSORY or
LOCK/OFF and the key is in the ignition.
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Retained Accessory Power (RAP)
These vehicle accessories can be used for up to
20 minutes after the engine is turned off:
Audio System
Power Windows
Overhead Console
Sunroof (if equipped)
These features will work when the key is in ON/RUN
or ACC/ACCESSORY. Once the key is turned from
ON/RUN to LOCK/OFF, these features continue to work
for up to 20 minutes, or until a door is opened.
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.
Starting Procedure
1. With your foot off the accelerator pedal, turn the
ignition to START. When the engine starts, let go of
the key. The idle speed will slow down as the engine
warms. 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, 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.
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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, repeat these steps. 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 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/retailer. If you do not, the
engine might not perform properly. Any resulting
damage would not be covered by the vehicle
warranty.Adjustable Throttle and Brake Pedal
If the vehicle has this feature, you can change the
position of the throttle and brake pedals.
The vehicle must be in P (Park) for this feature to
operate.
The switch used to adjust
the pedals is located on
the steering column.
Press the switch forward or backward to move the
pedals closer or farther away from you.
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Engine Coolant Heater
The engine coolant heater can provide easier starting
and better fuel economy during engine warm-up in cold
weather conditions at or below 0°F (−18°C). Vehicles
with an engine coolant heater should be plugged
in at least four hours before starting the 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 side of the engine
compartment next to the battery box facing
the engine.
3. Plug it 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 and prevent damage.
The length of time the heater should remain plugged in
depends on several factors. Ask a dealer/retailer in
the area where you will be parking the vehicle for the
best advice on this.
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Active Fuel Management™
The vehicle’s V8 engine may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders, depending
on driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate in the
half cylinder mode, allowing the vehicle to achieve better
fuel economy. When greater power is required, such
as accelerating from a stop, passing, or merging onto a
freeway, the system will maintain full-cylinder operation.
Automatic Transmission Operation
There are several different
positions for the gear shift
lever.
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P (Park):This position locks the rear wheels. It is the
best position to use when you start the engine because
the vehicle cannot move easily.
{CAUTION:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
rmly set. The vehicle can roll.
Do not leave the 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 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). SeeShifting Into
Park on page 2-34. If you are pulling a trailer, see
Towing a Trailer on page 4-46.
{CAUTION:
If you have four-wheel drive, the vehicle will be free
to roll — even if the shift lever is in P (Park) — if the
transfer case is in Neutral. So, be sure the transfer
case is in a drive gear — not in Neutral. See
Four-Wheel Drive on page 2-28. SeeShifting Into
Park on page 2-34.
Make sure the shift lever is fully in P (Park) before
starting the engine. The vehicle has an automatic
transmission shift lock control system. You have to fully
apply the brake pedal, then press the shift lever
button before you can shift from P (Park) when the
ignition key is in ON/RUN. If you cannot shift out
of P (Park), ease pressure on the shift lever and 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 on page 2-36.
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R (Reverse):Use this gear to back up.
Notice: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,
seeIf Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on page 4-30.
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.
{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, 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.Notice: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.
D (Drive):This position is for normal driving. It provides
the best fuel economy. If you need more power for
passing, and you are:
Going less than about 35 mph (55 km/h), push the
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
The vehicle will shift down to the next gear and have
more power.
Downshifting the transmission in slippery road conditions
could result in skidding, see “Skidding” underLoss of
Control on page 4-12.
D (Drive) can be used when towing a trailer, carrying a
heavy load, driving on steep hills, or for off-road driving.
You may want to shift the transmission to 3 (Third) or, if
necessary, a lower gear selection if the transmission
shifts too often.
3 (Third):This position is also used for normal driving. It
reduces vehicle speed more than D (Drive) without using
the brakes. You might choose 3 (Third) instead of
D (Drive) when driving on hilly, winding roads, when
towing a trailer, so there is less shifting between gears
and when going down a steep hill.
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To shift to the 3 (Third) position, you must rst press the
large button on the shift handle. While the button is
pressed, move the shifter in the 3 (Third) position.
2 (Second):This position reduces vehicle speed even
more than 3 (Third) without using the brakes. You can
use 2 (Second) on hills. It can help you control vehicle
speed as you go down steep mountain roads, as you use
your brakes off and on.
To shift to the 2 (Second) position, you must rst press
the large button on the shift handle. While the button is
pressed, move the shifter in the 2 (Second) position.
You can also use 2 (Second) for starting the vehicle from
a stop on slippery road surfaces.
1 (First):This position reduces vehicle speed even
more than 2 (Second) without using the brakes. You can
use it on very steep hills, or in deep snow or mud. If
the shift lever is put in 1 (First) while the vehicle
is moving forward, the transmission will not shift into
rst gear until the vehicle is going slowly enough.
To shift to the 1 (First) position, you must rst press the
large button on the shift handle. While the button is
pressed, move the shifter in the 1 (First) position.Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator pedal
may damage the transmission. The repair will not be
covered by the vehicle warranty. If you are stuck, do
not spin the tires. When stopping on a hill, use the
brakes to hold the vehicle in place.
Four-Wheel Drive
If the vehicle has four-wheel drive, the engine’s driving
power can be sent to all four wheels for extra traction.
Read the following before using four-wheel drive,
to become familiar with its operation. You should use
Two-Wheel High for most normal driving conditions.
Notice:Driving on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive Low for
an extended period of time may cause premature
wear on your vehicle’s powertrain. Do not drive on
clean, dry pavement in Four-Wheel-Drive High or
Four-Wheel-Drive Low for extended periods of time.
Notice:If you continually drive your vehicle with the
transfer case in AUTO or Four-Wheel Drive, you
could shorten the life of the transfer case or the
Four-Wheel Drive system. The selector switch should
be left in Two-Wheel Drive High mode. Only use
AUTO and Four-Wheel Drive when you need extra
traction such as in wet or slippery road conditions.
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