2005 HUMMER H2 engine

When starting your engine in very cold weather (below
0°F or−18°C), do this:
1. With your foot off the accelerator pedal, turn the
ignition key to START and hold it there up to
15 seconds. When the engine starts, let go of
the key.
2. If your engine still will not start, or starts but then
stops, it could be ooded with too much gasoline.
Try pushing your accelerator pedal all the way to the
oor and holding it there as you hold the key in
START for about three seconds. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briey but then stops again, do the
same thing, but this time keep the pedal down
for ve or six seconds. This clears the extra
gasoline from the engine.
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. If you do not, your engine
might not perform properly.Engine Coolant Heater
Your vehicle may be equipped with 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. Locate the electrical cord near the front recovery
loop on the driver’s side of the vehicle.
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. 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 in the area where you will be parking
your vehicle. The dealer can give you the best advice
for that particular area.
Automatic Transmission Operation
Your vehicle is equipped with an automatic transmission
and features an electronic shift position indicator
located within the instrument panel cluster.
There are several different positions for your shift lever.
PARK (P):This position locks your drive wheels. It
is the best position to use when you start your engine
because your vehicle cannot move easily.
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{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 2-37. If you are pulling a trailer, see
Towing a Trailer on page 4-68.
{CAUTION:
Your vehicle will be free to roll — even if your
shift lever is in PARK (P) — if your transfer
case is in NEUTRAL. So, be sure the transfer
case is in a drive gear — not in NEUTRAL. See
Shifting Into 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 You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-52.
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NEUTRAL (N):In this position, your engine does not
connect with the drive wheels. To restart when you
are already moving, use NEUTRAL (N) only.
{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.DRIVE (D):This position is for normal driving. If you
need more power for passing, and you are:
Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You will shift down to the next gear and have more
power.
DRIVE (D) 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
THIRD (3) or, if necessary, a lower gear selection if the
transmission shifts too often.
THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
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SECOND (2):This position gives you more power but
lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want to
use your brakes off and on.
If you manually select SECOND (2), the transmission
will drive in second gear. You may use this feature
for reducing the speed of the rear wheels when you are
trying to start your vehicle from a stop on slippery
road surfaces. Once the vehicle is moving, shift into
DRIVE (D).
FIRST (1):This position gives you even more power,
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST (1) while the vehicle is moving
forward, the transmission will not shift into rst gear
until the vehicle is going slowly enough.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
On cold days, approximately 32°F (0°C) or colder, your
transmission is designed to shift differently until the
engine reaches normal operating temperature. This is
intended to improve heater performance.Tow/Haul Mode
Your vehicle is equipped
with a tow/haul mode. The
button is located on the
instrument panel to the
right of the steering wheel.
You can use this feature to assist when towing or
hauling a heavy load. See “Tow/Haul Mode” under
Towing a Trailer on page 4-68for more information.
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All-Wheel Drive
All-wheel drive sends your engine’s driving power to all
four wheels for extra traction. To get the most out of
all-wheel drive, you must be familiar with its operation.
Notice:Driving on pavement in 4HI Lock or
4LO Lock for extended periods may cause
premature wear on your vehicle’s powertrain and
tires. Do not drive in 4HI Lock or 4LO Lock on
pavement for extended periods.
Transfer Case Buttons
The transfer case buttons
are located to the right of
the instrument panel
cluster. Use these switches
to shift into and out of the
different all-wheel drive
modes.You can choose between four modes:
G(4HI):This setting is used for driving in most street
and highway situations. You can also use this setting for
light or variable off-road conditions.
H(4HI Lock):Use this mode when you need extra
traction in most off-road situations such as sand, mud,
snow or level, rocky trails.
I(4LO Lock):This mode delivers extra torque to all
four wheels and is used for extreme off-road conditions.
You might choose 4LO Lock if you are driving off-road,
deep sand, mud, or snow and climbing or descending
steep hills.
When in this mode you can also choose to lock the rear
axle for additional traction in extreme off-road situations.
SeeLocking Rear Axle on page 4-10.
Notice:Operating your vehicle in 4LO Lock above
50 mph (80 km/h) for any extended period of time
could cause damage to the transfer case. Do
not operate your vehicle in 4LO Lock above 50 mph
(80 km/h) for extended periods.
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Shifting into 4LO Lock
To shift into 4LO Lock, the ignition must be in RUN and
the vehicle must be stopped or moving less than
2 mph (3.2 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the 4LO Lock button. You must wait for
the 4LO Lock indicator light to stop ashing and remain
lit before shifting your transmission in gear.
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
It is normal for your vehicle to have engagement noise
and bump when shifting between 4LO and 4HI
ranges or from NEUTRAL with the engine running.
If the 4LO Lock button is pressed when your vehicle is in
gear and/or moving, the 4LO Lock indicator light will ash
for 15 seconds and not complete the shift unless your
vehicle is moving less than 2 mph (3.2 km/h) and the
transmission is in NEUTRAL (N). After 15 seconds the
transfer case will return to the setting last chosen.
Shifting Out of 4LO Lock
To shift from 4LO Lock to 4HI or 4HI Lock, your vehicle
must be stopped or moving less than 2 mph (3.2 km/h)
with the transmission in NEUTRAL (N) and the ignition in
RUN. The preferred method for shifting out of 4LO
Lock is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4HI or 4HI Lock
button. You must wait for the 4HI or 4HI Lock indicator
light to stop ashing and remain lit before shifting your
transmission into gear.
It is normal for your vehicle to have engagement noise
and bump when shifting between 4LO and 4HI
ranges or from NEUTRAL with the engine running.
If the 4HI or 4HI Lock button is pressed when your
vehicle is in gear and/or moving, the 4HI or 4HI Lock
indicator light will ash for 15 seconds but will not
complete the shift unless your vehicle is moving less
than 2 mph (3.2 km/h) and the transmission is in
NEUTRAL (N).
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
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Shifting into NEUTRAL
To shift the transfer case to NEUTRAL, do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake.
3. Start the vehicle or turn the ignition to RUN.
4. Connect the vehicle to the towing vehicle.
5. Put the transmission in NEUTRAL (N).
6. Shift the transfer case to 4HI.
7. Simultaneously press and hold the 4HI and
4LO Lock buttons for 10 seconds. The red
NEUTRAL light will come on when the transfer case
shift to NEUTRAL is complete.
8. Turn the ignition to LOCK.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift the transfer case out of NEUTRAL, do the
following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (4HI, 4HI Lock or 4LO Lock).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. You may start the engine and shift the transmission
to the desired position.
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
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