2004 CHEVROLET MONTE CARLO Owners Manual

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:Modications 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.
Modications 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 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
may damage the emission control system on your
vehicle. Diagnosis and service may be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required. United States
Canada
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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 “If the Light Is On Steady” 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 “If the Light Is On Steady”
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. SeeFilling 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.
SeeGasoline Octane on page 5-4. 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, misring, 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.
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.
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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 is
designed 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.
Oil Pressure Indicator Light
The oil pressure indicator
tells you if you have the
correct oil pressure in your
engine to operate your
vehicle.
Under normal conditions the indicator should read
slightly above the half way point.
If your oil pressure falls too low, the indicator will read
at the low setting in the red zone.3800 V6 Engine
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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:
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.
Cruise Control Light
The CRUISE light comes
on whenever you set your
cruise control. SeeCruise
Control on page 3-11. United StatesCanada
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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 may move while cornering,
braking or accelerating. 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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Message Center
The message center is located below the tachometer
gage on the instrument panel cluster. It gives you
important safety and maintenance facts.
Service Traction System Warning
Message
If your vehicle is equipped with the traction control
system and this message appears when you are driving,
there is a problem with your traction control system
and your vehicle is in need of service.
When this message is displayed, the system will not limit
wheel spin. The message will stay on for 60 seconds.
Four chimes will also be heard. Adjust your driving
accordingly.When the ignition is turned off, this message will be
displayed again for three seconds to remind you
that your traction control system is not working properly.
Be sure to have your vehicle serviced right away.
Traction Active Message
If your vehicle is equipped with the traction control
system, this message will stay on a few seconds after
the traction system stops limiting wheel spin.
This message will appear when the traction control
system is limiting wheel spin. United States
Canada
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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. SeeEngine Coolant on page 5-31,Engine Coolant
Temperature Gage on page 3-38andEngine
Overheating on page 5-34for further information.
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Low Oil Pressure Message
This message is displayed when the engine oil pressure
is low. A chime will sound continuously, also. See Oil
Pressure Indicator Light on page 3-41.
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.
SeeEngine Oil on page 5-18on how to check the oil
level and for what type of oil to add. United States
CanadaUnited StatesCanada
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