2007 HUMMER H3 engine

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 stoppes 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 or LOCK 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.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. If you do not, your engine might not
perform properly. Any resulting damage would
not be covered by your vehicle’s warranty.
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Engine Coolant Heater
Your vehicle may have this feature.
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 0F (−18C) as noted on the cord.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located in the engine compartment
behind the underhood fuse block 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.
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Automatic Transmission Operation
The automatic transmission has a shift lever on
the console.
It features an electronic shift position indicator
within the instrument cluster. This display must be
powered anytime the shift lever is capable of
being moved out of PARK (P). This means that if
your key is turned off, but not in LOCK, there
will be a small current drain on your battery which
could discharge your battery over a period of
time. If you need to leave your key in the ignition
but not in LOCK for an extended period, it is
recommended that you disconnect the battery
cable from the battery to prevent discharging your
battery.
There are several different positions for your shift
lever.PARK (P):This position locks your rear wheels.
It is the best position to use when you start the
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) (Automatic
Transmission) on page 117. If you are
pulling a trailer, seeTowing a Trailer on
page 297.
106

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 brakes 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 and 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. See
Shifting Out of Park (P) (Automatic Transmission)
on page 119
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 286.NEUTRAL (N):In this position, your engine does
not connect with the 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.
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Manual Transmission Operation
This is your shift
pattern.
Here is how to operate your manual transmission:
FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal
as you slowly press down on the accelerator pedal.
You can shift into FIRST (1) when you are going
less than 20 mph (30 km/h). If you have come to a
complete stop and it is hard to shift into FIRST (1),
put the shift lever in NEUTRAL and let up on the
clutch. Then press the clutch pedal back down and
shift into FIRST (1).SECOND (2):Press the clutch pedal as you
let up on the accelerator pedal and shift into
SECOND (2). Then, slowly let up on the clutch
pedal as you press the accelerator pedal.
THIRD, FOURTH AND FIFTH (3, 4 and 5):
Shift into THIRD (3), FOURTH (4) and FIFTH (5)
the same way you do for SECOND (2). Slowly
let up on the clutch pedal as you press the
accelerator pedal.
To stop, let up on the accelerator pedal and press
the brake pedal. Just before the vehicle stops,
press the clutch pedal and the brake pedal,
and shift to NEUTRAL.
NEUTRAL:Use this position when you start or
idle your engine.
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Full-Time Four-Wheel Drive
Full-Time Four-Wheel Drive sends your engine’s
driving power to all four wheels for extra traction.
To get the most out of Full-Time Four-Wheel
Drive, you must be familiar with its operation.
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
Full-Time Four-Wheel Drive modes.You can choose between four modes:
4
m(Four-Wheel High):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.
N (NEUTRAL):Shift the vehicle’s transfer case
to NEUTRAL only when towing your vehicle.
SeeRecreational Vehicle Towing on page 295
orTowing Your Vehicle on page 294for more
information.
Notice:Driving on pavement in Four-Wheel
High Lock or Four Wheel Low Lock for
extended periods may cause premature wear
on your vehicle’s powertrain and tires. Do not
drive in Four-Wheel High Lock or Four-Wheel
Low Lock on pavement for extended periods.
4
mQ(Four-Wheel-High Lock):Use this
mode when you need extra traction in most
off-road situations such as sand, mud, snow or
level, rocky trails.
111

Shifting into Four-Wheel Low Lock
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.
To shift into Four-Wheel-Low Lock, the ignition
must be in ON and the vehicle must be stopped or
moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). The preferred
method for shifting into Four-Wheel Low is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).
Press and release the Four-Wheel-Low Lock
button. If your vehicle has a manual transmission,
the clutch pedal must be pressed to the oor while
you press the Four-Wheel-Low Lock button, or the
shift will not be completed. You must wait for the
Four-Wheel-Low Lock indicator light to stop
ashing and remain lit before shifting your
transmission in gear.
It is normal for your vehicle to have engagement
noise and bump when shifting between
Four-Wheel Low and Four-Wheel High ranges or
from NEUTRAL with the engine running.If the Four-Wheel-Low Lock button is pressed
when your vehicle is in gear and/or moving
too fast, the Four-Wheel-Low Lock indicator light
will ash for 15 seconds and not complete the shift
unless your vehicle is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).
After 15 seconds the transfer case will return to
the last chosen setting.
Shifting Out of Four-Wheel-Low Lock
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.
To shift out of Four-Wheel-Low Lock, your
vehicle must be stopped or moving less
than 3 mph (5 km/h) with the transmission
in NEUTRAL (N) and the ignition in ON.
The preferred method for shifting out of
Four-Wheel-Low Lock is to have your
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).
113

Press and release the Four-Wheel High or
Four-Wheel-High Lock button. If your vehicle has
a manual transmission, the clutch pedal must
be pressed to the oor while you press the
Four-Wheel High or Four-Wheel-High Lock
button, or the shift will not be completed.
You must wait for the Four-Wheel High or
Four-Wheel-High 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
Four-Wheel Low and Four-Wheel High ranges
or from NEUTRAL with the engine running.
If the Four-Wheel High or Four-Wheel-High Lock
button is pressed when your vehicle is in gear
and/or moving too fast, the Four-Wheel High
or Four-Wheel-High Lock indicator light will ash
for 15 seconds but will not complete the shift
unless your vehicle is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).Shifting Into NEUTRAL
To shift the transfer case to NEUTRAL, do the
following:
1. Set the parking brake.
2. Start the vehicle by turning the ignition to
START.
3. Put the transmission in NEUTRAL (N).
If your vehicle has a manual transmission,
press and hold the clutch pedal down
while you perform Steps 5 through 9.
4. Shift the transfer case to Four-Wheel High.
{CAUTION:
Shifting an all-wheel-drive vehicle’s
transfer case into NEUTRAL can cause
your vehicle to roll even if the automatic
transmission is in PARK (P) or the manual
transmission is in any gear. You or others
could be injured. Make sure the parking
brake is rmly set before you shift the
transfer case to NEUTRAL.
114