2008 PONTIAC GRAND PRIX Owners Manual

Starting the Engine
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.
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.
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. 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 ACC/ACCESSORY or
LOCK/OFF 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 let the cranking motor cool down.
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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:The 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/retailer. If you do not, your engine
might not perform properly. Any resulting damage
would not be covered by your vehicle’s warranty.Engine Coolant Heater
The engine coolant heater, if available, can help in
cold weather conditions at or below 0°F (−18°C)
for easier starting and better fuel economy during
engine warm-up. Plug in the coolant heater at least
four hours before starting your vehicle. An internal
thermostat in the plug-end of the cord may exist
which will prevent engine coolant heater operation
at temperatures above 0°F (−18°C).
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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 above the engine air
cleaner/lter. SeeEngine Compartment
Overview on page 5-12for more information
on location.
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, making sure to
keep it away from moving engine parts. If this is
not done, the cord could be damaged.
How long should the coolant heater be kept plugged in?
The answer depends on the outside temperature, the
kind of oil that is in the vehicle, and some other things.
Instead of trying to list everything here, we ask that
you contact your dealer/retailer in the area where the
vehicle will be parked. The dealer/retailer can give
you the best advice for that particular area.
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Active Fuel Management™
Your vehicle’s engine may be equipped with Active
Fuel Management™. 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.
Automatic Transmission Operation
The shift lever for the automatic transmission is
located on the console between the seats.
Maximum engine speed is limited when the vehicle
is in PARK (P) or NEUTRAL (N) to protect driveline
components from improper operation.
There are several
different positions
for the shift lever.
PARK (P):This position locks the front wheels.
It is the best position to use when the engine is
started because the vehicle cannot move easily.3800 V6 Engine
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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 2-34. If you are pulling a trailer,
seeTowing a Trailer on page 4-29.Make sure the shift lever is fully in PARK (P) before
starting the engine. The vehicle has an automatic
transmission shift lock control system. You must fully
apply your regular brakes rst and then press the
shift lever button, located on the front of the shift lever,
before you can shift from PARK (P) when the ignition
key is in RUN. If the vehicle cannot be shifted out
of PARK (P), ease pressure on the shift lever by pushing
it 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. SeeShifting Out of
PARK (P) on page 2-35.
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 the vehicle back and forth to get out of snow,
ice or sand without damaging the transmission, see
If Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on page 4-21.
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NEUTRAL (N):In this position, the engine does not
connect with the wheels. To restart when the vehicle
is already moving, use NEUTRAL (N) only. Also,
use NEUTRAL (N) when the vehicle is being towed.
{CAUTION:
Shifting into a drive gear while the 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 the vehicle needs more power for passing, and it is:
Going less than 35 mph (55 km/h),
push the accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more,
push the accelerator pedal all the way down.
The vehicle will shift down to the next gear
and have more power.
Downshifting the transmission in slippery road conditions
could result in skidding, see Skidding underLoss of
Control on page 4-12.
Notice:If your vehicle seems to start up rather
slowly or not shift gears when you go faster, and
you continue to drive your vehicle that way, you
could damage the transmission. Have your vehicle
serviced right away. You can drive in SECOND (2)
when you are driving less than 35 mph (55 km/h)
and DRIVE (D) for higher speeds until then.
THIRD (3):This position is also used for normal driving.
However, it reduces vehicle speed more than DRIVE (D)
without using your brakes. You might choose THIRD (3)
instead of DRIVE (D) when driving on hilly, winding
roads, when towing a trailer, so there is less shifting
between gears, when going down a steep hill and when
driving on non-highway scenarios (i.e. city streets etc.).
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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
the vehicle’s speed as it goes down steep mountain
roads, but then you would also want to use the brakes
off and on.
Notice:Driving in SECOND (2) for more than
25 miles (40 km) or at speeds over 55 mph (90 km/h),
can cause damage to your engine and/or
transmission. Also, shifting into SECOND (2) at
speeds above 65 mph (105 km/h) can cause damage.
Drive in DRIVE (D) instead of SECOND (2).
FIRST (1):This position reduces vehicle speed even
more than SECOND (2) without using your brakes.
It can be used on very steep hills, or in deep snow
or mud. If the shift lever is moved to 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.Performance Shifting with TAP-Shift®
If the vehicle is equipped with a 5.3L V8 engine,
it may have this feature. It allows you to change
gears similar to a manual transmission.
To fully use this feature, do the following:
1. The MANUAL (M) position can be selected while
the vehicle is moving. The current transmission
position will continue to be displayed on the
Driver Information Center (DIC) and Head-Up
Display (HUD), if equipped.
2. Move the shift lever
to the MANUAL (M).
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3. The paddles are
located on the steering
wheel. They are used to
up-shift or down-shift
the transmission.
4. Push either paddle once to up-shift to the next
gear. Pull either paddle once to down-shift to
the next gear.
The vehicle will begin moving in rst gear upon
acceleration. For better control in icy or slippery
conditions, the vehicle may start out in SECOND (2),
rather than FIRST (1). This will only occur if you
have “tapped up” to second gear.
The up-shift light on the
instrument panel cluster,
or the up-shift symbol on
the HUD, if equipped, is
given as a prompt to use
the TAP-Shift
®paddle.For more information, seeUp-Shift Light on page 3-45
The up-shift light will only appear in the instrument
panel cluster if the HUD is off or if the vehicle does
not have HUD.
This prompt to up-shift, as needed, will be given
throughout acceleration. If up-shifting does not occur
when prompted, the vehicle speed will be limited
to protect the engine.
The gear position will display on the DIC and HUD,
if equipped, when in manual mode.
Pressing the accelerator while driving in the highest
gear (FOURTH (4)) between 20 mph (32 km/h)
and 50 mph (80 km/h), will make the transmission
automatically downshift. As your speed gets closer to
50 mph (80 km/h), you will need to increase accelerator
pedal travel to get the vehicle to downshift. At 50 mph
(80 km/h), even with the accelerator fully depressed,
the transmission will always remain in FOURTH (4).
The transmission will also automatically downshift as
the vehicle decelerates and comes to a stop.
If a paddle is pushed or pulled and the vehicle cannot
respond to a transmission gear change, a chime will
sound. The system will not allow either an up-shift or a
down-shift if the vehicle speed is too fast or too slow,
nor will it allow a start from THIRD (3) or higher gear.
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