2004 GMC ENVOY XL engine

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline 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.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 SERVICE
ENGINE SOON or 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.
3-45

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).
{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.
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused
by a dangerously low oil level or other problems causing
low oil pressure. United States
Canada
3-46

Change Engine Oil Light
When this light comes on, it means that service is
required for your vehicle. SeeScheduled Maintenance
on page 6-4andEngine Oil on page 5-16for more
information.
Once the engine oil has been changed, the change
engine oil light must be reset. Until it is reset, the light
will be displayed when the engine is on.
Security Light
This light will come on briey when you turn the key
toward START. 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 2-19.
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 dealer.
Also, seeContent Theft-Deterrent on page 2-17for
additional information regarding the SECURITY light. United States
CanadaUnited StatesCanada
3-47

Cruise Control Light
Your vehicle may have this feature. The CRUISE light
appears whenever you set your cruise control.
Reduced Engine Power Light
This light is displayed when a noticeable reduction in the
vehicle’s performance may occur. The vehicle may be
driven at a reduced speed when the reduced engine
power light is on but acceleration and speed may be
reduced. The performance may be reduced until the next
time you drive your vehicle. If this light stays on, see your
dealer as soon as possible for diagnosis and repair.
This light may also come on if there is a problem with the
Electronic Throttle Control (ETC) system. If this happens,
take the vehicle in for service as soon as possible.
Service Four-Wheel Drive
Warning Light
This light should come on briey when you turn on the
ignition, as a check to show you it is working. United States
Canada
United StatesCanada
United StatesCanada
3-48

The SERVICE 4WD light comes on to indicate that
there may be a problem with the drive system and
service is required. Malfunctions can be indicated by the
system before any problem is apparent, which may
prevent serious damage to the vehicle. This system is
also designed to assist your service technician in
correctly diagnosing a malfunction.
Check Gages Warning Light
The CHECK GAGES 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.
Gate Ajar Light
If this light comes on, your liftgate or liftglass is ajar.
Try closing the liftgate or liftglass again. Never drive
with the liftgate or liftglass even partially open.
United States
Canada
United StatesCanada
3-49

Fuel Gage
When the ignition is on, the fuel gage tells you about
how much fuel you have remaining.Here are four things that some owners ask about. None
of these show a problem with your fuel gage:
At the gas station, the gas pump shuts off before
the gage reads full.
It takes a little more or less fuel to ll up than the
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.
Low Fuel Warning Light
The light next to the fuel gage will come on briey when
you are starting the engine.
This light comes on when the fuel tank is low on fuel.
To turn it off, add fuel to the fuel tank. SeeFuel on
page 5-4. United States
Canada
3-50

Driver Information Center (DIC)
Your vehicle may have this feature. The DIC display
is located on the instrument panel cluster above
the steering wheel. The DIC can display information
such as the trip odometer, fuel economy and
personalization features. The DIC buttons are located
on the steering wheel.
A.Trip Information:Press this button to display the
odometer, trip odometer and the timer.
B.Fuel Information:Press this button to display the
current range, average fuel economy, instant
fuel economy and engine oil life.C.Personalization:Press this button to change
personal settings for some of the options on your
vehicle.
D.Select:Press this button to reset certain functions
and turn off or acknowledge messages on the DIC.
DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display the current driver and the
information that was last displayed before the engine
was turned off.
If a problem is detected, a warning message will appear
on the display. Pressing the trip stem will acknowledge
any warning or service messages. Pressing any of
the DIC steering wheel buttons (Trip Information, Fuel
Information, Personalization or Select button) will
also acknowledge any warnings or service messages.
The DIC has different modes which can be accessed by
pressing the four buttons on the DIC. These buttons
are trip information, fuel information, personalization and
select. The button functions are detailed following.
Trip Information
Use the trip information button to scroll through the
odometer, TRIP A, TRIP B and TIMER.
3-51

Fuel Range
Press the fuel information button until RANGE appears
to display the remaining distance you can drive
without refueling. It’s based on fuel economy and the
fuel remaining in the tank. The display will show LOW if
the fuel level is low.
The fuel economy data used to determine fuel range is
an average of recent driving conditions. As your
driving conditions change, this data is gradually updated.
Fuel range cannot be reset.
Average Fuel Economy
Pressthe fuel information button until AVG appears in the
display. Average fuel economy is how many miles per
gallon your vehicle is getting based on current and past
driving conditions.
Press and hold the select button while AVG. ECON
is displayed to reset the average fuel economy. Average
fuel economy will then be calculated starting from that
point. If the average fuel economy is not reset, it will be
continually updated each time you drive.
Instant Fuel Economy
Press the fuel information button until INST appears in
the display. Instant fuel economy is how many miles
per gallon your vehicle is at the particular moment
in time. The instant fuel economy cannot be reset.
GM Oil Life System
Press the fuel information button until ENGINE OIL LIFE
appears in the display. The GM Oil Life System shows
an estimate of the oil’s remaining useful life. It will show
100% when the system is reset after an oil change.
It will alert you to change your oil on a schedule
consistent with your driving conditions.
Always reset the engine oil life monitor after an oil
change. To reset the monitor, press and hold the
select button while ENGINE OIL LIFE is displayed.
For more information, seeEngine Oil on page 5-16.
3-53