emission control CHEVROLET TAHOE 2005 2.G Owners Manual

Tire Pressure Light
If your vehicle is equipped
with the Tire Pressure
Monitor system, this light
will come on if the
system detects low tire
pressure.
A CHECK TIRE PRESSURE DIC message will
accompany the light.
This light will also come on for a bulb check when the
vehicle is started.
SeeTire Pressure Monitor System on page 5-67for
more information.
For more information on your tires, seeTires on
page 5-60.
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.
3-48

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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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.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.
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Fuel
Gasoline
The 8th digit of your vehicle identication number (VIN)
shows the code letter or number that identies your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identication
Number (VIN) on page 5-106.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also seeFuel E-85 (85% Ethanol) on page 5-6.Inall
other engines, use only regular unleaded gasoline.
Gasoline Octane
Use regular unleaded gasoline with a posted octane
of 87 or higher. If the octane is less than 87, you may
get a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you might damage
your engine. A little pinging noise when you accelerate
or drive uphill is considered normal. This does not
indicate a problem exists or that a higher-octane fuel is
necessary. If you are using 87 octane or higher-octane
fuel and hear heavy knocking, your engine needs
service.
Gasoline Specications
It is recommended that gasoline meet specications
which were developed by automobile manufacturers
around the world and contained in the World-Wide Fuel
Charter which is available from the Alliance of Automobile
Manufacturers at www.autoalliance.org/fuel_charter.htm.
Gasoline meeting these specications could provide
improved driveability and emission control system
performance compared to other gasoline.
California Fuel
If your vehicle is certied to meet California Emission
Standards, it is designed to operate on fuels that
meet California specications. See the underhood
emission control label. If this fuel is not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance may be affected. The malfunction indicator
lamp may turn on and your vehicle may fail a
smog-check test. SeeMalfunction Indicator Lamp on
page 3-48. If this occurs, return to your authorized GM
dealer for diagnosis. If it is determined that the
condition is caused by the type of fuel used, repairs
may not be covered by your warranty.
5-5

Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work
properly. In most cases, you should not have to add
anything to your fuel. However, some gasolines contain
only the minimum amount of additive required to
meet U.S. Environmental Protection Agency regulations.
General Motors recommends that you buy gasolines
that are advertised to help keep fuel injectors and intake
valves clean. If your vehicle experiences problems
due to dirty injectors or valves, try a different brand of
gasoline. Also, your GM dealer has additives that
will help correct and prevent most deposit-related
problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specications described earlier.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant where you buy
gasoline whether the fuel contains MMT. General Motors
does not recommend the use of such gasolines.
Fuels containing MMT can reduce the life of spark plugs
and the performance of the emission control system
may be affected. The malfunction indicator lamp
may turn on. If this occurs, return to your authorized GM
dealer for service.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identication number (VIN)
shows the code letter or number that identies your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identication
Number (VIN) on page 5-106.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also seeFuel on page 5-5. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.
Only vehicles that have the 5.3L V8 engine
(VIN Code Z) may use 85% ethanol fuel (E-85).
5-6

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-16. Reset oil life
system. SeeEngine Oil Life System on page 5-19.An Emission Control
Service.••
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter or change indicator (if equipped). If necessary,
replace lter. SeeEngine Air Cleaner/Filter on page 5-21.See footnote (l).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-70and “Tire Wear Inspection” inAt Least Once a Month on
page 6-10.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
6-5

Additional Required Services
The following services should be performed at the rst maintenance service (IorII) after the indicated miles
(kilometers) shown for each item.
Additional Required Services
Service and Miles (Kilometers)25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Inspect fuel system for damage or
leaks.• •••••
Inspect exhaust system for loose or
damaged components.• •••••
Vehicles without a lter restriction
indicator: Replace engine air cleaner
lter. SeeEngine Air Cleaner/Filter on
page 5-21.•••
Change automatic transmission uid
and lter (severe service).See
footnote (h).•••
Change automatic transmission uid
and lter (normal service).•
Four-wheel drive: Change transfer case
uid.See footnote (g).•••
Inspect evaporative control system.An
Emission Control Service. See
footnotes † and (k).•••
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Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Replace spark plugs and inspect spark
plug wires.An Emission Control
Service.•
Engine cooling system service (or every
ve years, whichever occurs rst).An
Emission Control Service. See
footnote (i).•
Inspect engine accessory drive belt.An
Emission Control Service. See
footnote (m).•
Maintenance Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.#Lubricate the front suspension, ball joints, steering
linkage, transmission shift linkage, and parking
brake cable guides. Ball joints should not be lubricated
unless their temperature is 10°F (-12°C) or higher,
or they could be damaged.
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.
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(j)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the uid level checked. Add uid if needed.
(k)Inspect system. Check all fuel and vapor lines and
hoses for proper hook-up, routing, and condition. Check
that the purge valve works properly, if equipped.
Replace as needed.
(l)If you drive regularly under dusty conditions, inspect
the lter at each engine oil change.
(m)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench
®dealer can assist
you with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel ll.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-16for further
details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
Engine Coolant Level Check
Check the engine coolant level and add
DEX-COOL®coolant mixture if necessary. SeeEngine
Coolant on page 5-26for further details.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer tank and add the proper uid if necessary.
6-9

Please contact your dealer for specic information about
availability. All Courtesy Transportation arrangements
will be administered by appropriate dealer personnel.
Canadian Vehicles:For warranty repairs during
the Complete Vehicle Coverage period of the General
Motors of Canada New Vehicle Limited Warranty,
alternative transportation may be available under the
Courtesy Transportation Program. Please consult
your dealer for details.
General Motors reserves the right to unilaterally modify,
change or discontinue Courtesy Transportation at
any time and to resolve all questions of claim eligibility
pursuant to the terms and conditions described
herein at its sole discretion.
Vehicle Data Collection and Event
Data Recorders
Your vehicle, like other modern motor vehicles, has a
number of sophisticated computer systems that monitor
and control several aspects of the vehicle’s performance.
Your vehicle uses on-board vehicle computers to monitor
emission control components to optimize fuel economy,to monitor conditions for airbag deployment and, if so
equipped, to provide anti-lock braking and to help the
driver control the vehicle in difficult driving situations.
Some information may be stored during regular
operations to facilitate repair of detected malfunctions;
other information is stored only in a crash event by
computer systems, such as those commonly called event
data recorders (EDR).
In a crash event, computer systems, such as the Airbag
Sensing and Diagnostic Module (SDM) in your vehicle
may record information about the condition of the vehicle
and how it was operated, such as data related to
engine speed, brake application, throttle position, vehicle
speed, safety belt usage, airbag readiness, airbag
performance, and the severity of a collision. If your
vehicle is equipped with Quadrasteer or StabiliTrak
®,
steering performance, including yaw rate, steering wheel
angle, and lateral acceleration, is also recorded. This
information has been used to improve vehicle crash
performance and may be used to improve crash
performance of future vehicles and driving safety. Unlike
the data recorders on many airplanes, these on-board
systems do not record sounds, such as conversation of
vehicle occupants.
7-9