engine CHEVROLET TAHOE 2008 3.G Service Manual

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 comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes 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.
If the Light is Flashing
The following can prevent more serious damage to
your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid 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 the vehicle.
Turn the ignition 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/retailer
for service as soon as possible.
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If the Light Is On Steady
You might 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 the Tank on page 5-10. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap allows 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 vehicle’s electrical system might be wet. The
condition is usually 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 5-6. 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
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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.
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.When the oil pressure reaches the low pressure zone,
the OIL PRESSURE LOW STOP ENGINE message
will appear in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-59and
Engine Oil on page 5-17for more information.
A reading in the low pressure zone may be caused
by a dangerously low oil level or some 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.
If your vehicle is a Two-mode Hybrid, see the
Two-mode Hybrid manual for more information. United States
Canada
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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 as a check to be
sure it works. If it does
not, have your vehicle
serviced.
If 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 2-21.
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 3-17for more information.
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The gage will rst indicate empty before you are out of
fuel, and you should get more fuel as soon as
possible.
When the fuel tank is low, the FUEL LEVEL LOW
message will appear in the Driver Information Center
(DIC). SeeDIC Warnings and Messages on page 3-59
for more information.
Here are some 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.
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
Low Fuel Warning Light
This light, under the fuel
gage, will come on briey
when you are starting
the engine.
This light and a chime will come on when the fuel tank
is low on fuel. There will also be a “FUEL LEVEL
LOW” message on the Driver Information Center, see
DIC Warnings and Messages on page 3-59for more
information. When you add fuel this light and message
should go off. If it does not, have your vehicle
serviced.
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Driver Information Center (DIC)
Your vehicle has a Driver Information Center (DIC).
The DIC displays information about your vehicle. It also
displays warning messages if a system problem is
detected.
All messages will appear in the DIC display located
below the tachometer in the instrument panel cluster.
The DIC comes on when the ignition is on. After a short
delay, the DIC will display the information that was
last displayed before the engine was turned off.
If your vehicle has DIC buttons, see “DIC Operation and
Displays (With DIC Buttons)” later in this section and
DIC Vehicle Customization (With DIC Buttons) on
page 3-67for the displays available.
If your vehicle does not have DIC buttons, see “DIC
Operation and Displays (Without DIC Buttons)” later in
this section for the displays available.
DIC Operation and Displays
(With DIC Buttons)
If your vehicle has DIC buttons, the information below
explains the operation of this system.
The DIC has different displays which can be accessed
by pressing the DIC buttons located on the instrument
panel, next to the steering wheel.
The DIC displays trip, fuel, and vehicle system
information, and warning messages if a system problem
is detected.
The DIC also allows some features to be customized.
SeeDIC Vehicle Customization (With DIC Buttons)
on page 3-67for more information.
If your vehicle has DIC buttons, you can also use the
trip odometer reset stem to view some of the DIC
displays. See “DIC Operation and Displays (Without DIC
Buttons)” later in this section.
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DIC Buttons
The buttons are the
trip/fuel, vehicle
information, customization,
and set/reset buttons.
The button functions are
detailed in the following
pages.
3(Trip/Fuel):Press this button to display the
odometer, trip odometer, fuel range, average economy,
fuel used, timer, and transmission temperature.
Some vehicles also display instantaneous economy
and an Active Fuel Management™ indicator.
T(Vehicle Information):Press this button to display
the oil life, units, tire pressure readings, engine hours,
and Remote Keyless Entry (RKE) transmitter
programming.
U(Customization):Press this button to customize the
feature settings on your vehicle. SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-67for more
information.
V(Set/Reset):Press this button to set or reset certain
functions and to turn off or acknowledge messages
on the DIC.
Trip/Fuel Menu Items
3
(Trip/Fuel):Press this button to scroll through the
following menu items:
Odometer
Press the trip/fuel button until ODOMETER displays.
This display shows the distance the vehicle has
been driven in either miles (mi) or kilometers (km).
Pressing the trip odometer reset stem will also display
the odometer.
To switch between English and metric measurements,
see “Units” later in this section.
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Fuel Used
Press the trip/fuel button until FUEL USED displays.
This display shows the number of gallons (gal) or
liters (L) of fuel used since the last reset of this menu
item. To reset the fuel used information, press and hold
the set/reset button while FUEL USED is displayed.
Timer
Press the trip/fuel button until TIMER displays. This
display can be used as a timer.
To start the timer, press the set/reset button while
TIMER is displayed. The display will show the amount
of time that has passed since the timer was last
reset, not including time the ignition is off. Time will
continue to be counted as long as the ignition is
on, even if another display is being shown on the DIC.
The timer will record up to 99 hours, 59 minutes
and 59 seconds (99:59:59) after which the display will
return to zero.
To stop the timer, press the set/reset button briey while
TIMER is displayed.
To reset the timer to zero, press and hold the set/reset
button while TIMER is displayed.
Transmission Temperature
Press the trip/fuel button until TRANS TEMP displays.
This display shows the temperature of the automatic
transmission uid in either degrees Fahrenheit (°F) or
degrees Celsius (°C).
Instantaneous Economy and Active Fuel
Management™ Indicator
If your vehicle has this display, press the trip/fuel button
until INST ECONOMY V8 MODE displays. This
display shows the current fuel economy at a particular
moment and will change frequently as driving conditions
change. This display shows the instantaneous fuel
economy in miles per gallon (mpg) or liters per
100 kilometers (L/100 km). Unlike average economy,
this screen cannot be reset.
An Active Fuel Management™ indicator will display on
the right side of the DIC, while INST ECONOMY displays
on the left side. Active Fuel Management™ allows the
engine to operate on either four or eight cylinders,
depending on your driving demands. When Active Fuel
Management™ is active, V4 MODE will display on the
DIC. When Active Fuel Management™ is inactive,
V8 MODE will display. SeeActive Fuel Management™
on page 2-29for more information.
Blank Display
This display shows no information.
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Vehicle Information Menu Items
T
(Vehicle Information):Press this button to scroll
through the following menu items:
Oil Life
Press the vehicle information button until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil’s remaining useful life. If you see 99% OIL LIFE
REMAINING on the display, that means 99% of the
current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-59. You should
change the oil as soon as you can. SeeEngine Oil on
page 5-17. In addition to the engine oil life system
monitoring the oil life, additional maintenance is
recommended in the Maintenance Schedule in this
manual. SeeScheduled Maintenance on page 6-4for
more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.
Also, be careful not to reset the OIL LIFE display
accidentally at any time other than when the oil hasjust been changed. It cannot be reset accurately until
the next oil change. To reset the engine oil life system,
seeEngine Oil Life System on page 5-20.
Units
Press the vehicle information button until UNITS
displays. This display allows you to select between
English or Metric units of measurement. Once in this
display, press the set/reset button to select between
ENGLISH or METRIC units. All of the vehicle information
will then be displayed in the unit of measurement
selected.
Tire Pressure
The pressure for each tire can be viewed in the DIC.
The tire pressure will be shown in either pounds
per square inch (psi) or kilopascals (kPa). Press the
vehicle information button until the DIC displays FRONT
TIRES PSI (kPa) LEFT ## RIGHT ##. Press the
vehicle information button again until the DIC displays
REAR TIRES PSI (kPa) LEFT ## RIGHT ##.
If a low or high tire pressure condition is detected by
the system while driving, a message advising you
to check the pressure in a specic tire will appear in
the display. SeeInflation - Tire Pressure on page 5-74
andDIC Warnings and Messages on page 3-59for
more information.
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If the tire pressure display shows dashes instead of a
value, there may be a problem with your vehicle. If this
consistently occurs, see your dealer/retailer for service.
Engine Hours
Press the vehicle information button until ENGINE
HOURS displays. This display shows the total number
of hours the engine has run.
Relearn Remote Key
This display allows you to match Remote Keyless
Entry (RKE) transmitters to your vehicle. To match
an RKE transmitter to your vehicle:
1. Press the vehicle information button until
PRESS
VTO RELEARN REMOTE KEY displays.
2. Press the set/reset button until REMOTE KEY
LEARNING ACTIVE is displayed.
3. Press and hold the lock and unlock buttons on
the rst transmitter at the same time for about
15 seconds.
On vehicles with memory recall seats, the
rst transmitter learned will match driver 1 and the
second will match driver 2.
A chime will sound indicating that the transmitter
is matched.4. To match additional transmitters at this time,
repeat Step 3.
Each vehicle can have a maximum of eight
transmitters matched to it.
5. To exit the programming mode, you must cycle
the key to LOCK/OFF.
Blank Display
This display shows no information.
DIC Operation and Displays
(Without DIC Buttons)
If your vehicle does not have DIC buttons, the
information below explains the operation of this system.
The DIC has different displays which can be accessed
by pressing the trip odometer reset stem located on the
instrument panel cluster. Pressing the trip odometer
reset stem will also turn off, or acknowledge, DIC
messages.
The DIC displays trip and vehicle system information,
and warning messages if a system problem is detected.
If your vehicle does not have DIC buttons, you can
use the trip odometer reset stem to view the following
displays: odometer, engine hours, trip odometer, oil life,
Remote Keyless Entry (RKE) transmitter programming,
and display language.
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