engine CHEVROLET IMPALA 2008 9.G Workshop Manual

requires service. If the problem does not clear after
restarting the vehicle, you should see your dealer/retailer
for service. SeeDIC Warnings and Messages on
page 3-52for more information.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. SeeAccessories and
Modifications on page 5-3for 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.The traction you can get in a curve depends on the
condition of the 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
antilock 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.
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.
If you need to reduce your speed as you approach a
curve, do it before you enter the curve, while the
front wheels are straight ahead.
4-9

Hydroplaning
Hydroplaning is dangerous. Water can build up under
your vehicle’s tires so they actually ride on the
water. This can happen if the road is wet enough and
you are going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.
There is no hard and fast rule about hydroplaning.
The best advice is to slow down when the road
is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving tips
include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping equipment in
good shape.
Keep the windshield washer uid reservoir lled.
Have good tires with proper tread depth.
SeeTires on page 5-54.
Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer/retailer before departing.
Things to check on your own include:
Windshield Washer Fluid:Reservoir full?
Windows clean — inside and outside?
Wiper Blades:In good shape?
Fuel, Engine Oil, Other Fluids:All levels checked?
Lamps:Do they all work and are lenses clean?
Tires:Are treads good? Are tires inated to
recommended pressure?
Weather and Maps:Safe to travel?
Have up-to-date maps?
Highway Hypnosis
Always be alert and pay attention to your surroundings
while driving. If you become tired or sleepy, nd a safe
place to park your vehicle and rest.
Other driving tips include:
Keep the vehicle well ventilated.
Keep interior temperature cool.
Keep your eyes moving — scan the road
ahead and to the sides.
Check the rearview mirror and vehicle
instruments often.
4-14

Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on at or rolling terrain. Tips for driving
in these conditions include the following.
Keep your vehicle serviced and in good shape.
Check all uid levels and brakes, tires, cooling
system, and transmission.
Going down steep or long hills, shift to a lower gear.
{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 and 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.
Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
Top of hills: Be alert — something could be in your
lane (stalled car, accident).
Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
4-15

If You Are Caught in a Blizzard
If you are stopped by heavy snow, you could be in a
serious situation. You should probably stay with
your vehicle unless you know for sure that you are near
help and you can hike through the snow. Here are
some things to do to summon help and keep yourself
and your passengers safe:
Turn on the hazard warning ashers.
Tie a red cloth to your vehicle to alert police that
you have been stopped by the snow.
Put on extra clothing or wrap a blanket around you.
If you do not have blankets or extra clothing, make
body insulators from newspapers, burlap bags,
rags, oor mats — anything you can wrap around
yourself or tuck under your clothing to keep warm.
You can run the engine to keep warm, but be careful.
4-18

{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. 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.
4-19

If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
Slowly and cautiously spin the wheels to free your
vehicle when stuck in sand, mud, ice, or snow.
SeeRocking Your Vehicle to Get It Out on page 4-20.
If your vehicle has a traction system, it can often help to
free a stuck vehicle. Refer to your vehicle’s traction
system in the Index. If the stuck condition is too severe
for the traction system to free the vehicle, turn the
traction system off and use the rocking method.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. The vehicle can overheat,
causing an engine compartment re or other
damage. Spin the wheels as little as possible
and avoid going above 35 mph (55 km/h) as
shown on the speedometer.
For information about using tire chains on your vehicle,
seeTire Chains on page 5-76.
Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right to clear
the area around the front wheels. Turn off any traction
system. SeeTraction Control System (TCS) on
page 4-6. Then shift back and forth between
REVERSE (R) and a forward gear, spinning the wheels
as little as possible. To prevent transmission wear,
wait until the wheels stop spinning before shifting gears.
Release the accelerator pedal while you shift, and
press lightly on the accelerator pedal when the
transmission is in gear. By slowly spinning the wheels in
the forward and reverse directions, you will cause a
rocking motion that could free your vehicle. If that does
not get your vehicle out after a few tries, it might
need to be towed out. If your vehicle does need to be
towed out, seeTowing Your Vehicle on page 4-26.
4-20

That is 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 will 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, do not drive over 50 mph (80 km/h) and
do not 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.
Do not 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
4-28

Hitches
It is important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads
are a few reasons why you will need the right hitch.
Here are some rules to follow:
The rear bumper on your vehicle is not intended
for hitches. Do not attach rental hitches or other
bumper-type hitches to it. Use only a frame-mounted
hitch that does not attach to the bumper.
Will you have to make any holes in the body of your
vehicle when you install a trailer hitch? If you do, then
be sure to seal the holes later when you remove the
hitch. If you do not seal them, deadly carbon
monoxide (CO) from your exhaust can get into your
vehicle. SeeEngine Exhaust on page 2-34. Dirt and
water can, too.
Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the
tongue of the trailer so that the tongue will not drop to
the road if it becomes separated from the hitch.
Instructions about safety chains may be provided by the
hitch manufacturer or by the trailer manufacturer.
Follow the manufacturer’s recommendation for attaching
safety chains and do not attach them to the bumper.Always leave just enough slack so you can turn with
your rig. And, never allow safety chains to drag on
the ground.
Trailer Brakes
Does your trailer have its own brakes? Be sure to read
and follow the instructions for the trailer brakes so you’ll
be able to install, adjust and maintain them properly.
If your vehicle has Antilock brakes, do not try to tap
into your vehicle’s brake system. If you do, both
brake systems will not work well, or at all.
Even if your vehicle does not have Antilock brakes,
do not tap into your vehicle’s brake system if
the trailer’s brake system will use more than
0.02 cubic inch (0.3 cc) of uid from your vehicle’s
master cylinder. If it does, both braking systems will
not work well. You could even lose your brakes.
Will the trailer brake parts take 3,000 psi (20 650 kPa)
of pressure? If not, the trailer brake system must not
be used with your vehicle.
If everything checks out this far, then make the brake
uid tap at the upper rear master cylinder port. But do
not use copper tubing for this. If you do, it will bend
and break off. Use steel brake tubing.
4-30

Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle may need additional
wiring. Check with your dealer/retailer. The arrows on
your instrument panel will ash whenever you signal
a turn or lane change. Properly hooked up, the trailer
lamps will also ash, telling other drivers you are about
to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It is
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you do not shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your
speed to around 45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating.Notice:When the outside temperature is above
100°F (38°C) and/or there is a steep, continuous
grade, the recommended speed when towing
is 55 mph (88 km/h) or less. Extended higher than
normal engine and transmission temperatures
may damage your vehicle.
If you have overdrive, you may want to drive in
THIRD (3) instead of DRIVE (D).
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here is
how to do it:
1. Apply your regular brakes, but do not shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
4-32

3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift to PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you are
pulling a trailer. See the Maintenance Schedule for
more on this. Things that are especially important in
trailer operation are automatic transmission uid (do not
overll), engine oil, drive belts, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If you
are trailering, it is a good idea to review this information
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-29.
4-33