engine CHEVROLET EXPRESS 2004 Owner's Manual

StabiliTrak Indicator Light
If you have the StabiliTrak
system, this light will be on
or ashing, according to
the description table for the
StabiliTrak
®system.
For more information, seeStabiliTrak
®System on
page 4-8.
You will hear three chimes if the light turns on and
one chime if the light turns off.
If this light remains on steady, your vehicle needs to be
taken in for service.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves into the red area your engine is
too hot!
It means that your engine coolant has overheated. If
you have been operating your vehicle under normal
operating conditions, you should pull off the road,
stop your vehicle, and turn off the engine as soon
as possible.
SeeEngine Overheating on page 5-24.
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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 awhile, 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,
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 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.
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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 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 5-8. The
diagnostic system can determine if the fuel cap hasbeen 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, 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 Gage
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure in
kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.United States
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A reading in the low pressure zone may be caused by a
dangerously low oil level or other problem causing
low oil pressure. Check your oil as soon as possible.
{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.
Change Engine Oil Light
This light is displayed
when your vehicle needs
to be serviced.
If your vehicle has a V8 engine and this light is ashing,
it indicates that the oil level is low.
When this light is on steady, your vehicle needs to be
serviced. SeeScheduled Maintenance on page 6-4
for more information.
Once the engine oil has been changed, the change
engine oil light must be reset. Until it is reset, the light
will stay on for a while each time the engine is
started. For more information on resetting the system,
see “How to Reset the Engine Oil Life System”
underEngine Oil Life System on page 5-16.
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Security Light
The light will stay on until the engine starts. If the light
ashes, the Passlock®System has entered a tamper
mode. If the vehicle fails to start, seePasslock®
on page 2-18.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
System. Your vehicle will not be protected by Passlock®,
and you should see your GM dealer.
Cruise Control Light
The cruise light comes on whenever you set your
cruise control. SeeCruise Control on page 3-10for
more information. United States
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Reduced Engine Power Light
If the check engine and
reduced engine power
lights are on, the throttle
may be disabled and
a noticeable reduction in
the vehicle’s performance
may occur.
If the reduced engine power light is on, but there is no
reduction in performance, proceed to your destination.
The performance may be reduced the next time
the vehicle is driven. The vehicle may be driven at a
reduced speed while the reduced engine power light is
on, but acceleration and speed may be reduced.
Anytime the check engine light stays on, the vehicle
should be taken to an authorized GM dealer as soon as
possible for service.
Highbeam On Light
This light will illuminate
when the headlamp high
beams are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8.
Daytime Running Lamps (DRL)
Indicator Light
You have this light on the
instrument panel. It will
light whenever the DRL are
on. It is also a reminder
to turn on your headlamps
when driving at night.
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Tow/Haul Mode Light
This message is displayed
when the tow/haul mode
has been activated.
For more information, see “Tow/Haul Mode” inTowing a
Trailer on page 4-34.
Check Gages Warning Light
This light will come on briey when you are starting
the engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil
pressure gages to see if they are in the warning zones.
Fuel Gage
The 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.
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Listed are four situations you may experience with your
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 moves a little when you turn a corner or
speed up.
The gage doesn’t go back to empty when you turn
off the ignition.
None of these indicate a problem with the fuel gage.
Audio System(s)
Notice:Before adding any sound equipment to
your vehicle, like a tape player, CB radio, mobile
telephone, or two-way radio, make sure that it can
be added by checking with your dealer. 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 improperly.
Figure out which audio system is in your vehicle, nd
out what your audio system can do, and how to operate
all of its controls.
Your vehicle may have 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 2-19for
more information.
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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 engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your 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.
Anti-Lock Brake System (ABS)
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-30.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.
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