2008 CHEVROLET IMPALA check engine

Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which monitors
operation of the fuel,
ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
make sure that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment. The check engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This can prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, the emission controls
might not work as well, your vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and could damage the emission control system on
your vehicle. Diagnosis and service might be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 5-6. Poor fuel quality
causes the engine not to run as efficiently as
designed. You might notice this as stalling after
start-up, stalling when you put the vehicle into gear,
misring, hesitation on acceleration, or stumbling
on acceleration — these conditions might go away
once the engine is warmed up. This will be detected by
the system and cause the light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light
turn off, your dealer/retailer can check the vehicle.
Your dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if you have recently replaced the battery or if the battery
has run down. The diagnostic system is designed to
evaluate critical emission control systems during normal
driving. This can take several days of routine driving.
If you have done this and your vehicle still does not pass
the inspection for lack of OBD system readiness, your
dealer/retailer can prepare the vehicle for inspection.
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Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
This light will come on
briey when you start your
engine. If it does not,
have your vehicle serviced.
When the light comes on and stays on, it means that oil
is not owing through your engine properly. You could
be low on oil and you might have some other system
problem.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent
on page 2-18.
Fog Lamp Light
The fog lamp light will
come on when the
fog lamps are in use.
The light will go out when the fog lamps are turned off.
SeeFog Lamps on page 3-16for more information.
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CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked.
This message also displays LEFT FRONT, RIGHT
FRONT, LEFT REAR, or RIGHT REAR to indicate which
tire needs to be checked. You can receive more than
one tire pressure message at a time. To read the other
messages that may have been sent at the same
time, press the set/reset button. If a tire pressure
message appears on the DIC, stop as soon as you can.
Have the tire pressures checked and set to those
shown on the Tire Loading Information label. SeeTires
on page 5-54,Loading Your Vehicle on page 4-21,
andInflation - Tire Pressure on page 5-61. The DIC also
shows the tire pressure values. SeeDIC Operation
and Displays on page 3-44. If the tire pressure is low,
the low tire pressure warning light comes on. See
Tire Pressure Light on page 3-38.
DRIVER DOOR OPEN
This message displays when the driver door is not
closed properly. Make sure that the door is closed
completely.
ENGINE HOT A/C (Air Conditioning) OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
To avoid added strain on a hot engine, the air
conditioning compressor is automatically turned off.
When the coolant temperature returns to normal, the A/C
operation automatically resumes. You can continue to
drive your vehicle. If this message continues to appear,
have the system repaired by your dealer/retailer as soon
as possible to avoid compressor damage.
ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating
on page 5-29for more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle to
idle until it cools down.
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STARTING DISABLED SERVICE
THROTTLE
This message displays if the starting of the engine is
disabled due to the electronic throttle control system.
Have your vehicle serviced by your dealer/retailer
immediately.
This message only appears while the ignition is in
ON/RUN, and will not disappear until the problem is
resolved.
This message cannot be acknowledged.
THEFT ATTEMPTED
This message displays if the content theft-deterrent
system has detected a break-in attempt while you were
away from your vehicle. SeeContent Theft-Deterrent
on page 2-18for more information.
TIGHTEN GAS CAP
This message may be displayed if the gas cap is not
on, or is not fully tightened. Check the gas cap to ensure
that it is on properly. SeeFilling the Tank on page 5-10
for more information.
TIRE LEARNING ACTIVE
This message displays when the Tire Pressure Monitor
System (TPMS) is re-learning the tire positions on
your vehicle. The tire positions must be re-learned after
rotating the tires or after replacing a tire or sensor.
SeeTire Inspection and Rotation on page 5-68,
Tire Pressure Monitor System on page 5-63, and
Inflation - Tire Pressure on page 5-61for more
information.
TRACTION CONTROL OFF
If your vehicle has the Traction Control System (TCS),
this message displays when the TCS turns off. See
Traction Control System (TCS) on page 4-6for more
information.
This message only displays while the ignition is in
ON/RUN and disappears after 10 seconds, unless it is
acknowledged or an urgent warning appears.
3-58

Audio System(s)
Determine which radio your vehicle has and then read the
pages following to familiarize yourself with its features.
{CAUTION:
This system provides you with far greater
access to audio stations and song listings.
Giving extended attention to entertainment
tasks while driving can cause a crash and you
or others can be injured or killed. Always keep
your eyes on the road and your mind on the
drive — avoid engaging in extended searching
while driving.
Keeping your mind on the drive is important for safe
driving. SeeDefensive Driving on page 4-2. Here are
some ways in which you can help avoid distraction
while driving.While your vehicle is parked:
Familiarize yourself with all of its controls.
Familiarize yourself with its operation.
Set up your audio system by presetting your
favorite radio stations, setting the tone, and
adjusting the speakers. Then, when driving
conditions permit, you can tune to your favorite
radio stations using the presets and steering wheel
controls if the vehicle has them.
Notice:Before adding any sound equipment to
your vehicle, such as an audio system, CD player,
CB radio, mobile telephone, or two-way radio, make
sure that it can be added by checking with your
dealer/retailer. Also, check federal rules covering
mobile radio and telephone units. If sound
equipment can be added, it is very important to do
it properly. Added sound equipment may interfere
with the operation of your vehicle’s engine,
radio, or other systems, and even damage them.
Your vehicle’s systems may interfere with the
operation of sound equipment that has been added.
Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, the audio system can be
played even after the ignition is turned off. SeeRetained
Accessory Power (RAP) on page 2-23for more
information.
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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 might 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 could 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 can take longer to stop and
the brake pedal will be harder to push.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. SeeAccessories and
Modifications on page 5-3.Antilock Brake System (ABS)
Your vehicle might have the Antilock 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.
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 front wheel
and at both rear wheels.
4-4

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.
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