engine CHEVROLET IMPALA 2007 9.G Workshop Manual

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. The brakes may not have time to
cool between hard stops. The 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 vehicle’s engine ever stops while you are
driving, brake normally but do not pump the
brakes. If you do, the pedal may get harder to
push down. If the 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.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 296.Anti-Lock Brake System (ABS)
Your vehicle might have the Anti-Lock Brake
System (ABS), an advanced electronic braking
system that will help prevent a braking skid.
If your vehicle has ABS,
this warning light on
the instrument
panel cluster will come
on briey when you
start your vehicle.
When you start the engine, or when you begin to
drive away, ABS will check itself. You might hear a
momentary motor or clicking noise while this test is
going on, and you might even notice that the brake
pedal moves or pulses a little. This is normal.
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Traction Control System (TCS)
Your vehicle may have a traction control system
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 transmission
and apply the front brakes to limit wheel spin.
This light will ash
when your traction
control system is
limiting wheel spin.
You may feel or hear the system working, but this
is normal.
If your 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 you to safely
use it again, you may re-engage the cruise
control. SeeCruise Control on page 157.The traction control system operates in all
transmission shift lever positions. But the system
can upshift the transmission only as high as
the shift lever position you’ve chosen, so you
should use the lower gears only when necessary.
SeeAutomatic Transaxle Operation on page 116.
When the system is on,
this warning light will
come on and stay on to
let you know if there’s
a problem.
A SERVICE TRACTION CONTROL message will
also appear on the DIC. When this warning
light is on, the system will not limit wheel spin.
Adjust your driving accordingly. SeeDIC Warnings
and Messages on page 199for more information.
To limit wheel spin, especially in slippery road
conditions, you should always leave the traction
control system on. But you can turn the system off
if you ever need to. You should turn the system
off if your vehicle ever gets stuck in sand, mud or
snow and rocking the vehicle is required.
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SeeRocking Your Vehicle to Get It Out on
page 277andIf Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow on page 276for more
information.
To turn the system on
or off, press the traction
control button located
on the left side of
the instrument panel.
When you turn the system off, a chime will sound,
the traction control warning light will come on
and stay on and a TRACTION CONTROL OFF
message will appear on the DIC. If the traction
control system is limiting wheel spin when
you press the button to turn the system off,
the warning light will come on and the system
will turn off right away.
You can turn the system back on at any time by
pressing the button again. The traction control light
should go off.
Adding non-dealer/non-retailer accessories can
affect your vehicle’s performance. SeeAccessories
and Modications on page 296for more
information.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.
Steering Tips
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.
257

Driving Through Deep Standing Water
Notice:If you drive too quickly through
deep puddles or standing water, water can
come in through the engine’s air intake
and badly damage the 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.
CAUTION: (Continued)
CAUTION: (Continued)
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 351.
266

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?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough
for long-distance driving? Are the tires
all inated to the recommended pressure?
Weather Forecasts:What is the weather
outlook along your route? Should you
delay your trip a short time to avoid a major
storm system?
Maps:Do you have up-to-date maps?
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Highway Hypnosis
Is there actually such a condition as highway
hypnosis? Or is it just plain falling asleep at the
wheel? Call it highway hypnosis, lack of
awareness, or whatever.
There is something about an easy stretch of road
with the same scenery, along with the hum of the
tires on the road, the drone of the engine, and the
rush of the wind against the vehicle that can make
you sleepy. Do not let it happen to you! If it does,
your vehicle can leave the road in less than a
second, and you could crash and be injured.
What can you do about highway hypnosis?
First, be aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with
a comfortably cool interior.
Keep your eyes moving. Scan the road ahead
and to the sides. Check your rearview mirrors
and your instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get
some exercise, or both. For safety, treat
drowsiness on the highway as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different
from driving in at or rolling terrain.
If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that
can make your trips safer and more enjoyable.
Keep your vehicle in good shape. Check
all uid levels and also the brakes, tires,
cooling system, and transaxle. These parts
can work hard on mountain roads.
270

{CAUTION:
If you do not shift down, the brakes could
get so hot that they would not work well.
You would then have poor braking or
even none going down a hill. You could
crash. Shift down to let the engine assist
the brakes on a steep downhill slope.
{CAUTION:
Coasting downhill in NEUTRAL (N) or with
the ignition off is dangerous. The brakes
will have to do all the work of slowing
down. They could get so hot that they
would not work well. You would then have
poor braking or even none going down a
hill. You could crash. Always have the
engine running and your vehicle in gear
when you go downhill.
Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when
you go down a steep or long hill.
Know how to go uphill. You may want to shift
down to a lower gear. The lower gears help
cool your engine and transaxle, and you can
climb the hill better.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not swing wide
or cut across the center of the road. Drive at
speeds that let you stay in your own lane.
As you go over the top of a hill, be alert. There
could be something in your lane, like a stalled
car or an accident.
You may see highway signs on mountains that
warn of special problems. Examples are long
grades, passing or no-passing zones, a falling
rocks area, or winding roads. Be alert to these
and take appropriate action.
271

You can run the engine to keep warm, but be
careful.
{CAUTION:
Snow can trap exhaust gases under
your vehicle. This can cause deadly CO
(carbon monoxide) gas to get inside.
CO could overcome you and kill you.
You cannot see it or smell it, so you might
not know it is in your vehicle. Clear away
snow from around the base of your
vehicle, especially any that is blocking
the exhaust pipe. And check around again
from time to time to be sure snow does
not collect there.
Open a window just a little on the side of
the vehicle that is away from the wind.
This will help keep CO out.
Run the engine only as long as you must.
This saves fuel. When you run the engine, make it
go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat
that you get and it keeps the battery charged.
275

You will need a well-charged battery to restart the
vehicle, and possibly for signaling later on with
the headlamps. Let the heater run for a while.
Then, shut the engine off and close the window
almost all the way to preserve the heat. Start
the engine again and repeat this only when you
feel really uncomfortable from the cold. But do it as
little as possible. Preserve the fuel as long as
you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
In order to free your vehicle when it is stuck, you
will need to spin the wheels, but you do not
want to spin your wheels too fast. The method
known as rocking can help you get out when you
are stuck, but you must use caution.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or
others could be injured. And, the
transaxle or other parts of the vehicle can
overheat. That could cause an engine
compartment re or other damage. When
you are stuck, spin the wheels as little as
possible. Do not spin the wheels above
35 mph (55 km/h) as shown on the
speedometer.
Notice:Spinning the wheels can destroy parts
of your vehicle as well as the tires. If you
spin the wheels too fast while shifting
the transaxle back and forth, you can destroy
the transaxle. SeeRocking Your Vehicle to
Get It Out on page 277.
For information about using tire chains on your
vehicle, seeTire Chains on page 372.
276

But trailering is different than just driving your
vehicle by itself. Trailering means changes in
handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to
be used properly.
That’s the reason for this part. In it are many
time-tested, important trailering tips and safety
rules. Many of these are important for your safety
and that of your passengers. So please read
this section carefully before you pull a trailer.
Load-pulling components such as the engine,
transmission, wheel assemblies and tires
are forced to work harder against the drag of the
added weight. The engine is required to operate
at relatively higher speeds and under greater
loads, generating extra heat. What’s more,
the trailer adds considerably to wind resistance,
increasing the pulling requirements.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed
limit restrictions, having to do with trailering.
Make sure your rig will be legal, not only where
you live but also where you’ll be driving.
A good source for this information can be
state or provincial police.
Consider using a sway control. You can ask a
hitch dealer/retailer about sway controls.
Don’t tow a trailer at all during the rst
1,000 miles (1 600 km) your new vehicle
is driven. Your engine, axle or other parts
could be damaged.
Then, during the rst 500 miles (800 km) that
you tow a trailer, don’t drive over 50 mph
(80 km/h) and don’t make starts at full throttle.
This helps your engine and other parts of
your vehicle wear in at the heavier loads.
Obey speed limit restrictions when towing a
trailer. Don’t drive faster than the maximum
posted speed for trailers, or no more than
55 mph (90 km/h), to save wear on your
vehicle’s parts.
Three important considerations have to do
with weight:
the weight of the trailer
the weight of the trailer tongue
and the total weight on your vehicle’s tires
285