2007 GMC YUKON XL engine

If the engine still does not start, and the key
appears to be undamaged, try another ignition key.
At this time, you may also want to check the fuse,
seeFuses and Circuit Breakers on page 540.Ifthe
engine still does not start with the other key, your
vehicle needs service. If your vehicle does start, the
rst key may be faulty. See your dealer who can
service the PASS-Key
®III+ to have a new key
made. In an emergency, contact Roadside
Assistance.
It is possible for the PASS-Key
®III+ decoder to
“learn” the transponder value of a new or
replacement key. Up to nine additional keys may
be programmed for the vehicle. The following
procedure is for programming additional keys only.
If all the currently programmed keys are lost or
do not operate, you must see your dealer or
a locksmith who can service PASS-Key
®III+ to
have keys made and programmed to the system.
See your dealer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the
system.To program the new additional key do the
following:
1. Verify that the new key has a
1stamped on it.
2. Insert the original, already programmed, key
in the ignition and start the engine. If the
engine will not start, see your dealer
for service.
3. After the engine has started, turn the key to
OFF, and remove the key.
4. Insert the new key to be programmed and turn
it to the RUN position within ve seconds of
removing the original key.
5. The security light will turn off once the key
has been programmed.
6. Repeat Steps 1 through 5 if additional keys
are to be programmed.
If you are driving and the security light comes on
and stays on, you may be able to restart your
engine. Your PASS-Key
®III+ system, however,
may not be working properly and must be serviced
by your dealer.
If you lose or damage your PASS-Key
®III+ key,
see your dealer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
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Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an
elaborate break-in. But it will perform better in
the long run if you follow these guidelines:
Keep your speed at 55 mph (88 km/h)
or less for the rst 500 miles (805 km).
Do not drive at any one constant speed,
fast or slow, for the rst 500 miles
(805 km). Do not make full-throttle starts.
Avoid downshifting to brake, or slow,
the vehicle.
Avoid making hard stops for the rst
200 miles (322 km) or so. During this time
your new brake linings are not yet broken
in. Hard stops with new linings can mean
premature wear and earlier replacement.
Follow this breaking-in guideline every time
you get new brake linings.
Do not tow a trailer during break-in. See
Towing a Trailer on page 405for the trailer
towing capabilities of your vehicle and more
information.
Following break-in, engine speed and load can
be gradually increased.
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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.
Notice: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.
D (START):This position starts the engine.
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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 these features, the sunroof and OnStar
®
System, will work when the ignition key is in
RUN or ACCESSORY. Once the key is turned
from RUN to LOCK, these features will continue
to work for up to 10 minutes or until a door is
opened.
Starting the Engine
Move your shift lever to PARK (P) or
NEUTRAL (N). Your engine will not start in
any other position — that is a safety feature.
To restart when you are 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.
Your vehicle has a Computer-Controlled
Cranking System. This feature assists in
starting the engine and protects the electrical
system. If the ignition key is turned to the
START position, and then released when the
engine begins cranking, the engine will continue
cranking until the vehicle starts or until it
exceeds the maximum cranking time allowed,
approximately 15 seconds to prevent cranking
motor damage. To prevent gear damage, this
system also prevents cranking if the engine is
already running. The 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. Waiting about 15 seconds
between each try, to allow the cranking motor to
cool down, will prevent damage due to
overheating.
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2. If the engine does not 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 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. 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.
The switch used to
adjust the pedals is
located on the center
console 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.
This feature is designed for shorter drivers, since
the pedals can not move farther away from
the standard position, but can move toward the
driver for better pedal reach.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 13for 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.
Displacement on Demand™ (DoD™)
Your vehicle’s V8 engine may have Displacement
on Demand™ (DoD™). This system allows the
engine to operate on either all or half of its
cylinders, depending on your 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.
141

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).
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).
SeeShifting Into Park (P) on page 152.If
you are pulling a trailer, seeTowing a
Trailer on page 405.
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