engine CHEVROLET TAHOE 2007 3.G User Guide

Ignition Positions
Use the key to turn the ignition switch to four
different positions.
A (LOCK):This position locks the ignition and
transmission. It is a theft-deterrent feature. You will
only be able to remove the key when the ignition is
turned to LOCK.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 it is, turn the steering wheel left and
right while you turn the key hard. If none of this
works, then your vehicle needs service.
B (ACCESSORY):This position lets you use
things like the radio and the windshield wipers when
the engine is off.
Lengthy operation of features such as the radio in
the ACCESSORY ignition position and the RUN
position may drain the battery and prevent your
vehicle from starting. Do not operate your vehicle in
the ACCESSORY ignition position for a long period
of time.
C (RUN):This is the position for driving. It is the
position the switch returns to after the engine starts,
and you release the key.
The battery could be drained if you leave the key in
the ACCESSORY or 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.
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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)
Your vehicle has a Retained Accessory Power
(RAP) feature which will allow certain features on
your vehicle to continue to work up to 10 minutes
after the ignition key is turned to LOCK.
The radio, power windows, and if the vehicle has a
sunroof and the OnStar
®System, will work when
the ignition key is in RUN or ACCESSORY. Once
the key is turned from RUN to LOCK, the windows
and sunroof will continue to work until a door is
opened. The radio will continue to work for up to
10 minutes or until the driver’s door is opened.
Starting the Engine
To place the transmission in the proper gear:
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.
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.
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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 ACCESSORY 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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Adjustable Throttle and Brake Pedal
If your vehicle has this feature, you can change
the position of the throttle and brake pedals.
This feature is designed for shorter drivers, since
the pedals cannot move farther away from the
standard position, but can move toward the driver
for better pedal reach.
The switch used to
adjust the pedals is
located on the
instrument panel below
the climate control
system.
Press the arrow at the bottom of the switch to
move the pedals closer to your body. Press
the arrow at the top of the switch to move the
pedals away from your body.No adjustment to the pedals can be made when
the vehicle is in REVERSE (R) or while using
the cruise control.
Your vehicle may have a memory function which
allows pedal settings to be saved and recalled.
SeeMemory Seat, Mirrors, and Pedals on page 13
for more information.
Engine Coolant Heater
Your vehicle may have 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. Open the hood and unwrap the electrical
cord. The cord is located on the driver’s
side of the engine compartment, near
the power steering 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 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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Active Fuel Management™
Your 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 the 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 your vehicle to
achieve better fuel economy. When greater
power demands are required, such as accelerating
from a stop, passing, or merging onto a freeway,
the system will maintain full-cylinder operation.
Your vehicle has an Active Fuel Management™
indicator. For more information on using this
display seeDIC Operation and Displays (With DIC
Buttons) on page 261orDIC Operation and
Displays (Without DIC Buttons) on page 267.
Automatic Transmission Operation
There are several different positions for the
shift lever.
Your vehicle has an automatic transmission with
an electronic shift position indicator within the
instrument panel cluster. This display will show the
position anytime the shift lever is moved out of
PARK (P).
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PARK (P):This position locks your rear 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). See
Shifting Into Park (P) on page 157.Ifyou
are pulling a trailer, seeTowing a Trailer
on page 422.
{CAUTION:
If you have four-wheel drive, 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, two-wheel
high, four-wheel high or four-wheel
low — not in NEUTRAL. SeeShifting Into
Park (P) on page 157.
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 404.
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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 two-wheel
drive vehicle is being towed.
{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. It
provides the best fuel economy for your vehicle. If
you need more power for passing, and you are:
Going less than about 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.
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.
Downshifting the transmission in slippery road
conditions could result in skidding, see “Skidding”
underLoss of Control on page 371
THIRD (3):This position is also used for normal
driving. However, it reduces vehicle speed
more than DRIVE (D) without using your brakes.
You can use THIRD (3) 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.
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SECOND (2):This position reduces vehicle speed
even more than THIRD (3) without using your
brakes. 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 select SECOND (2) and the Tow/Haul has
not been selected, the transmission will drive
in SECOND (2) 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.
If you select SECOND (2) and the Tow/Haul has
also been selected, the transmission operation will
be limited to FIRST (1) and SECOND (2) gears.
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.
FIRST (1):This position reduces vehicle speed
even more than SECOND (2) without using
your brakes. 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. The repair will not be covered by
your warranty. If you are stuck, do not spin
the tires. When stopping on a hill, use the
brakes to hold the vehicle in place.
When temperatures are very cold, the
Hydra-Matic
®Automatic Transmission’s gear
shifting may be delayed providing more stable
shifts until the engine warms up. Shifts may
be more noticeable with a cold transmission. This
difference in shifting is normal.
The transmission torque converter clutch operation
is restricted during cold operation. When the
startup transmission temperature is approximately
64°F (18°C) your torque converter clutch will
temporarily not operate. Once the transmission
temperature rises above 68°F (20°C), normal
operation will resume.
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Four-Wheel Drive
If your vehicle has four-wheel drive, you can send
your engine’s driving power to all four wheels
for extra traction. Read the part that follows before
using four-wheel drive.
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.
While driving on clean dry pavement and during
tight turns, you may experience a vibration in
the steering system.
Front Axle Locking Feature
The front axle locks and unlocks automatically
when you shift the transfer case. Some delay for
the axle to lock or unlock is normal.
Automatic Transfer Case
The transfer case knob
is located to the left of
the instrument panel
cluster.
Your vehicle has Four Wheel Drive with
StabiliTrak
®. For information on StabiliTrak®, see
StabiliTrak®System on page 363.
Use this dial to shift into and out of four-wheel
drive.
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