2004 HUMMER H2 engine

Starting Your Engine
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine won’t start in any other position – that’s a
safety feature. To restart when you’re 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.
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.
Notice:Holding your key in START for longer than
15 seconds at a time will cause your battery to be
drained much sooner. And the excessive heat can
damage your starter motor. Wait about 15 seconds
between each try to help avoid draining your battery
or damaging your starter.
2. If it doesn’t start within 10 seconds, push the
accelerator pedal all the way to the oor, while you
hold the ignition key in START. When the engine
starts, let go of the key and let up on the accelerator
pedal. Wait about 15 seconds between each try.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 won’t 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.
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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’ll 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.
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 don’t, 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’ll be parking your
vehicle. The dealer can give you the best advice for that
particular area.
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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’s
the best position to use when you start your engine
because your vehicle can’t 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
CAUTION: (Continued)
CAUTION: (Continued)
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 2-30. If you are pulling a trailer, see
Towing a Trailer on page 4-75.
{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 2-30.
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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,
see If You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-56.
NEUTRAL (N):In this position, your engine doesn’t
connect with the drive wheels. To restart when you’re
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.
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DRIVE (D):This position is for normal driving. If you
need more power for passing, and you’re:
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’ll 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).
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 won’t 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.
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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 4-75for more information.
All-Wheel Drive
All-wheel drive sends your engine’s driving power to all
four wheels for extra traction. To get the most
satisfaction 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.
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Shifting into 4HI or 4HI Lock
With the vehicle traveling less than 40 mph (64 km/h),
press and release the 4HI or 4HI Lock button. The
indicator light will ash while shifting. It will remain
illuminated when the shift is complete.
It may be necessary to drive backwards for a short
distance of 25 feet (7.5 m) to get the lock feature
to disengage.
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
illuminated 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 lights stops ashing before putting
the transmission back in gear.It is typical for your vehicle to exhibit signicant
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 illuminated before
shifting your transmission into gear.
It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting between
4LO and 4HI ranges or from NEUTRAL with the engine
running.
2-27

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 lights stops ashing before putting
the transmission back in gear.
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 lights stops ashing before putting
the transmission back in gear.
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