2005 PONTIAC GRAND PRIX engine

Braking
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake pedal.
That is perception time. Then you have to bring up your
foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds or
more with another. Age, physical condition, alertness,
coordination and eyesight all play a part. So do alcohol,
drugs and frustration. But even in three-fourths of a
second, a vehicle moving at 60 mph (100 km/h) travels
66 feet (20 m). That could be a lot of distance in an
emergency, so keeping enough space between
your vehicle and others is important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it is pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied.
Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This
is a mistake. Your brakes may not have time to
cool between hard stops. Your brakes will wear
out much faster if you do a lot of heavy braking.If you keep pace with the traffic and allow realistic
following distances, you will eliminate a lot of
unnecessary braking. That means better braking and
longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.
Anti-Lock Brake System (ABS)
Your vehicle may have anti-lock brakes. ABS is an
advanced electronic braking system that will help
prevent a braking skid.
If your vehicle has anti-lock
brakes, this warning light
on the instrument panel will
come on briey when
you start your vehicle.
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When you start your engine, or when you begin to drive
away, your anti-lock brake system will check itself.
You may hear a momentary motor or clicking noise while
this test is going on, and you may even notice that
your brake pedal moves or pulses a little. This is normal.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:A computer senses that wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each wheel.
The anti-lock system can change the brake pressure
faster than any driver could. The computer is
programmed to make the most of available tire and
road conditions. This can help you steer around
the obstacle while braking hard.
As you brake, your computer keeps receiving updates on
wheel speed and controls braking pressure accordingly.
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Traction Control System (TCS)
If the vehicle has the 3800 Supercharged V6 engine, it
has a Traction Control System (TCS) that limits wheel
spin. This is especially useful in slippery road conditions.
The system operates only if it senses that one or both of
the front wheels are spinning or beginning to lose
traction. When this happens, the system works the front
brakes and reduces engine power to limit wheel spin.
This symbol, along
with the TRACTION
CONTROL ACTIVE
message, comes on the
DIC screen when the
system is active.
You may feel or hear the system working, but this
is normal.
When the traction control
system is not working, this
symbol will come on the
instrument panel cluster.This symbol, along with
the message TRACTION
CONTROL OFF will
display in the DIC for
three seconds when the
traction control system
is disabled.
If there is a problem with the system, the service
traction system will also appear on the DIC. When these
symbols and messages appear on the instrument
panel and the DIC, the system will not limit wheel spin.
Adjust driving accordingly.
The traction control system automatically comes on
whenever the vehicle is started. To limit wheel spin,
especially in slippery road conditions, always leave the
system on. But the traction control system can be turned
off if needed. The system should be turned off if the
vehicle ever gets stuck in sand, mud, or snow and rocking
the vehicle is required. SeeRocking Your Vehicle to Get
It Out on page 4-33andIf You Are Stuck: In Sand, Mud,
Ice or Snow on page 4-32for more information.
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Press the traction
control button located
on the console to turn
the system off.
If the system is limiting wheel spin when the traction
control button is pressed, the system will turn off
instantly. Turn the system back on at any time by
pressing the button again.
If the vehicle is in cruise control when the traction
control system begins to limit wheel spin, the cruise
control will automatically disengage. When road
conditions allow safe use of it, the cruise control can be
used again. SeeCruise Control on page 3-10.Enhanced Traction System (ETS)
If the vehicle has the 3800 V6 engine and anti-lock
brakes, it may have an Enhanced Traction System
(ETS) that limits wheel spin. This is especially useful in
slippery road conditions. The system operates only if
it senses that one or both of the front wheels are
spinning or beginning to lose traction. When this
happens, the system reduces engine power and may
also upshift the transaxle to limit wheel spin.
This symbol comes on
the Driver Information
Center (DIC) when
the ETS is limiting
wheel spin.
If the vehicle is in cruise control when ETS begins to
limit wheel spin, the cruise control will automatically
disengage. When road conditions allow safe use of it,
the cruise control can be used again. SeeCruise Control
on page 3-10.
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Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Variable Effort Steering
If your vehicle has this steering system, the system
provides less steering effort for parking and when driving
at speeds below 20 mph (32 km/h). Steering effort will
increase at higher speeds for improved road feel.
Steering Tips
Driving on Curves
It is important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here is why:
Experienced driver or beginner, each of us is subject
to the same laws of physics when driving on curves.
The traction of the tires against the road surface
makes it possible for the vehicle to change its path
when you turn the front wheels. If there is no traction,
inertia will keep the vehicle going in the same direction.
If you have ever tried to steer a vehicle on wet ice,
you will understand this.The traction you can get in a curve depends on the
condition of your tires and the road surface, the angle
at which the curve is banked, and your speed. While you
are in a curve, speed is the one factor you can control.
Suppose you are steering through a sharp curve.
Then you suddenly apply the brakes. Both control
systems — steering and braking — have to do their
work where the tires meet the road. Unless you
have four-wheel anti-lock brakes, adding the hard
braking can demand too much of those places.
You can lose control.
The same thing can happen if you are steering through
a sharp curve and you suddenly accelerate. Those
two control systems — steering and acceleration — can
overwhelm those places where the tires meet the
road and make you lose control. SeeTraction Control
System (TCS) on page 4-9orEnhanced Traction
System (ETS) on page 4-10.
What should you do if this ever happens? Ease up on
the brake or accelerator pedal, steer the vehicle the way
you want it to go, and slow down.
Speed limit signs near curves warn that you should
adjust your speed. Of course, the posted speeds
are based on good weather and road conditions. Under
less favorable conditions you will want to go slower.
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Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not overdriving
those conditions. But skids are always possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, your wheels
are not rolling. In the steering or cornering skid, too
much speed or steering in a curve causes tires to slip
and lose cornering force. And in the acceleration
skid, too much throttle causes the driving wheels
to spin.
A cornering skid is best handled by easing your foot off
the accelerator pedal.
If you do not have the Enhanced Traction System or the
Traction Control System, or if the system is off, then
an acceleration skid is also best handled by easing your
foot off the accelerator pedal.
If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle to go. If you start steering quickly enough,
your vehicle may straighten out. Always be ready
for a second skid if it occurs.Of course, traction is reduced when water, snow, ice,
gravel, or other material is on the road. For safety, you
will want to slow down and adjust your driving to
these conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration,
or braking, including engine braking by shifting to a
lower gear. Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your vehicle is skidding. Learn to recognize warning
clues — such as enough water, ice, or packed snow
on the road to make a mirrored surface — and
slow down when you have any doubt.
If you have the anti-lock braking system, remember: It
helps avoid only the braking skid. If you do not have
anti-lock, then in a braking skid, where the wheels are
no longer rolling, release enough pressure on the brakes
to get the wheels rolling again. This restores steering
control. Push the brake pedal down steadily when
you have to stop suddenly. As long as the wheels are
rolling, you will have steering control.
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Hydroplaning usually happens at higher speeds. There
just is not a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage
your engine. Never drive through water that is
slightly lower than the underbody of your vehicle.
If you cannot avoid deep puddles or standing water,
drive through them very slowly.
Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong forces.
If you try to drive through owing water, as you
might at a low water crossing, your vehicle can
be carried away. As little as six inches of
owing water can carry away a smaller vehicle.
If this happens, you and other vehicle
occupants could drown. Do not ignore police
warning signs, and otherwise be very cautious
about trying to drive through owing water.
Some Other Rainy Weather Tips
Besides slowing down, allow some extra following
distance. And be especially careful when you
pass another vehicle. Allow yourself more clear
room ahead, and be prepared to have your
view restricted by road spray.
Have good tires with proper tread depth. SeeTires
on page 5-58.
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Once you are moving on the freeway, make certain you
allow a reasonable following distance.
Expect to move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your exit, do
not, under any circumstances, stop and back up. Drive
on to the next exit.
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted. Reduce your speed
according to your speedometer, not to your sense
of motion. After driving for any distance at higher
speeds, you may tend to think you are going slower
than you actually are.Before Leaving on a Long Trip
Make sure you are ready. Try to be well rested. If you
must start when you are not fresh — such as after
a day’s work — do not plan to make too many miles that
rst part of the journey. Wear comfortable clothing
and shoes you can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it is ready to go. If it needs
service, have it done before starting out. Of course, you
will nd experienced and able service experts in GM
dealerships all across North America. They will be ready
and willing to help if you need it.
Here are some things you can check before a trip:
Windshield Washer Fluid:Is the reservoir full?
Are all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you checked
all levels?
Lamps:Are they all working? Are the lenses clean?
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