2003 CHEVROLET IMPALA engine

Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped with 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
assure 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 may 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, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice:Modi®cations made to the engine,
transaxle, 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 may cause this light to come on.
Modi®cations to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
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 doesn't come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
·Light FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may
be required. United States
Canada
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·Light On SteadyÐ An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:
·Reducing vehicle speed.
·Avoiding hard accelerations.
·Avoiding steep uphill grades.
·If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops ¯ashing and remains on steady, see ªIf
the Light Is On Steadyº following.
If the light continues to ¯ash, when it is safe to do so,
stop the vehicle.
Find a safe place to park your vehicle. Turn the key off,
wait at least 10 seconds and restart the engine. If
the light remains on steady, see ªIf the Light Is On
Steadyº following. If the light is still ¯ashing, follow the
previous steps, and see your dealer for service as soon
as possible.
If the Light Is on Steady
You also may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. See
Filling Your Tank on page 5-7. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, mis®ring, hesitation
on acceleration or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
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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 can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to ®x any
mechanical or electrical problems that may have
developed.
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may 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 your battery or if your
battery has run down. The diagnostic system isdesigned to evaluate critical emission control systems
during normal driving. This may 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 GM dealer can prepare the
vehicle for inspection.
Cruise Control Light
Tthe CRUISE light comes
on whenever you set your
cruise control. See
ªCruise Controlº under
Turn Signal/Multifunction
Lever on page 3-7.
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Fuel GageThe fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage will ®rst indicate empty before you are out of
fuel, and you should get more fuel as soon as
possible.
Here are four situations you may experience with your
fuel gage. None of these indicate a problem with the fuel
gage.
·At the gas station, the fuel pump shuts off before
the gage reads full.
·It takes a little more or less fuel to ®ll up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank's
capacity to ®ll the tank.
·The gage goes back to empty when you turn off the
ignition.
·The gage pointer moves while cornering, braking or
acceleration.
Message Center
The message center is located below the temperature
gage or the tachometer gage (if equipped) on the
instrument panel cluster. It gives you important safety
and maintenance facts. United States-3400 V6
Engine Cluster
United States-3800 V6
Engine Cluster
Canada-3400 V6 Engine
ClusterCanada-3800 V6 Engine
Cluster
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Battery Warning Message
When the vehicle is started
this message will be
displayed for three
seconds.
If the message is displayed when the engine is running,
you may have a problem with your charging system.
If there is a problem with the charging system, four
chimes will sound when the message comes on. The
battery display will also stay on while the key is in
ON until the engine is started.
If the message stays on after starting the engine it could
indicate a problem with the generator drive belt, or
some other charging system problem. Have it checked
right away. Driving with this message on could drain
your battery.
If you must drive a short distance with this message
displayed, it helps to turn off all your accessories.
Hot Coolant Temperature Warning
Message
This message is displayed when the cooling
system temperature gets hot. A chime will sound
continuously, also.
Check the coolant temperature gage and the coolant
level. See
Engine Coolant on page 5-27,Engine Coolant
Temperature Gage on page 3-36andEngine
Overheating on page 5-30for further information.
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Low Oil Pressure Message
This message is displayed in the message center when
the engine oil pressure is low. A chime will sound
continuously, also.
If this occurs, you should have your vehicle serviced
immediately.
{CAUTION:
Don't 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:Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Low Engine Oil Level Message
Your vehicle may be equipped with a low engine oil
level message.
This message is displayed for 60 seconds at the start of
each ignition cycle when the engine oil level is low.
Four chimes will also sound.
When the ignition is turned off, this message will be
displayed again for three seconds to remind you
that your engine oil level is low. Be sure to have your
vehicle serviced right away.
See
Engine Oil on page 5-16on how to check the oil
level and for what type of oil to add. United States
Canada
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Change Engine Oil Message
This message is displayed when the engine oil needs to
be changed. It will appear for 60 seconds.
Once the engine oil has been changed, the CHANGE
ENGINE OIL message must be reset. Until it is
reset, this message will be displayed for 60 seconds
each time you start the engine. For more information on
resetting the system, see ªHow to Reset the Change
Engine Oil Messageº under
Engine Oil on page 5-16.
Low Tire Message
Your vehicle may be equipped with the tire pressure
system which monitors the in¯ation pressure of the tires.
After the system has ªlearnedº the tire pressure with
properly in¯ated tires, the LOW TIRE PRESSURE
message will be displayed and four warning chimes will
sound if the tire pressure in one tire becomes 12 psi
(83 kPa) lower than the other three tires.
When you have checked the tire pressures, be sure to
reset the tire in¯ation monitor. See ªTire Pressure
Monitor Systemº under
Tires on page 5-61. United States
CanadaUnited StatesCanada
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Service Vehicle Soon Message
This message will come on if you have engine problems.
These problems may not be obvious and may not
affect vehicle performance or durability. Consult a
quali®ed dealership for necessary repairs to maintain
top vehicle performance.
Highbeam Out Warning Message
If this message appears, you may have a problem with
your high-beam headlamps.
The message will stay on about 60 seconds. When the
ignition is turned off, this message will be displayed
again for three seconds to remind you that you
may have a problem with your highbeam-headlamps.
Be sure to check your bulbs right away and replace
them if necessary.
See
Bulb Replacement on page 5-56. United States
CanadaUnited StatesCanada
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