2009 CHEVROLET TAHOE check engine

This vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-96.
Keep a record with all parts receipts and list the mileage
and the date of any service work performed. See
Maintenance Record on page 6-17.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect the
airow around it. This can cause wind noise and can
affect fuel economy and windshield washer performance.
Check with your dealer/retailer before adding equipment
to the outside of the vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of this vehicle. To help keep the
engine clean and maintain optimum vehicle performance,
we recommend the use of gasoline advertised as TOP
TIER Detergent Gasoline.
The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-113.If the vehicle has the 5.3L V8 engine (VIN Code 0), the
5.3L V8 engine (VIN Code 3), or the 6.2L V8 engine
(VIN Code 2–), you can use either unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E85). See
Fuel E85 (85% Ethanol) on page 5-7. In all other
engines, use only unleaded gasoline. SeeGasoline
Octane on page 5-5.
Gasoline Octane
For all vehicles except those with the 6.2L V8 engine
(VIN Code 2), use regular unleaded gasoline with
a posted octane rating of 87 or higher. If the octane
rating is less than 87, you might notice an audible
knocking noise when you drive, commonly referred to
as spark knock. If this occurs, use a gasoline rated at
87 octane or higher as soon as possible. If you are using
gasoline rated at 87 octane or higher and you hear
heavy knocking, the engine needs service.
If the vehicle has the 6.2L V8 engine (VIN Code 2), use
premium unleaded gasoline with a posted octane rating
of 91 or higher. You can also use regular unleaded
gasoline rated at 87 octane or higher, but the vehicle’s
acceleration could be slightly reduced, and you might
notice a slight audible knocking noise, commonly referred
to as spark knock. If the octane is less than 87, you
might notice a heavy knocking noise when you drive.
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If this occurs, use a gasoline rated at 87 octane or higher
as soon as possible. Otherwise, you could damage the
engine. If you are using gasoline rated at 87 octane or
higher and you hear heavy knocking, the engine needs
service.
Gasoline Specications
At a minimum, gasoline should meet ASTM specication
D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in
Canada. Some gasolines contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend against the use of
gasolines containing MMT. SeeAdditives on page 5-6for
additional information.
California Fuel
If the vehicle is certied to meet California Emissions
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, the vehicle will operate
satisfactorily on fuels meeting federal specications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and the
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-43. If this occurs, return to yourauthorized dealer/retailer for diagnosis. If it is determined
that the condition is caused by the type of fuel used,
repairs might not be covered by the vehicle warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, you should not have to add anything to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if the vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS is
the only gasoline additive recommended by General
Motors.
Also, your dealer/retailer has additives that will help
correct and prevent most deposit-related problems.
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Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in the
vehicle. Static electricity discharge from the
container can ignite the fuel vapor. You can be
badly burned and the vehicle damaged if this
occurs. To help avoid injury to you and others:
Dispense fuel only into approved containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed, or on
any surface other than the ground.
Bring the ll nozzle in contact with the inside
of the ll opening before operating the nozzle.
Contact should be maintained until the lling
is complete.
Do not smoke while pumping fuel.
Do not use a cellular phone while
pumping fuel.
Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing, and tools away from any
underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts and
start a re. These include liquids like fuel, oil,
coolant, brake uid, windshield washer and other
uids, and plastic or rubber. You or others could
be burned. Be careful not to drop or spill things
that will burn onto a hot engine.
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A.Engine Air Cleaner/Filter on page 5-20.
B. Coolant Surge Tank and Pressure Cap. SeeCooling
System on page 5-28.
C. Remote Positive (+) Terminal. SeeJump Starting on
page 5-44.
D.Battery on page 5-43.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
F. Automatic Transmission Dipstick. See “Checking the
Fluid Level” underAutomatic Transmission Fluid
(6-Speed Transmission) on page 5-22orAutomatic
Transmission Fluid (4-Speed Transmission) on
page 5-25.
G. Remote Negative (−) Terminal (Out of View).
SeeJump Starting on page 5-44.
H. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-15.
I. Engine Cooling Fan. SeeCooling System on
page 5-28.
J. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-37.
K. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-40.L.Underhood Fuse Block on page 5-118.
M. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-39.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-14for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
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Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet GM Standard
GM6094M are all that is needed for good performance
and engine protection.
Engine oil system ushes are not recommended and
could cause engine damage not covered by the vehicle
warranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and lter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system
must be reset every time the oil is changed.When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A CHANGE ENGINE OIL SOON message comes on.
SeeDIC Warnings and Messages on page 3-64. Change
the oil as soon as possible within the next 600 miles
(1 000 km). It is possible that, if driving under the best
conditions, the oil life system might not indicate that an oil
change is necessary for over a year. However, the engine
oil and lter must be changed at least once a year and at
this time the system must be reset. Your dealer/retailer
has trained service people who will perform this work
using genuine parts and reset the system. It is also
important to check the oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, the oil must be
changed at 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system whenever
the oil is changed.
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Automatic Transmission Fluid
(6-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission uid
level. The only reason for uid loss is a transmission leak
or overheating the transmission. If you suspect a small
leak, then use the following checking procedures to check
the uid level. However, if there is a large leak, then it
may be necessary to have the vehicle towed to a dealer/
retailer service department and have it repaired before
driving the vehicle further.
Notice:Use of the incorrect automatic transmission
uid may damage the vehicle, and the damages may
not be covered by the vehicle’s warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-13.Change the uid and lter at the intervals listed in the
Maintenance Schedule. SeeScheduled Maintenance on
page 6-4. Be sure to use the transmission uid listed
inRecommended Fluids and Lubricants on page 6-13.
How to Check Automatic Transmission
Fluid
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
parts or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission uid.
Before checking the uid level, prepare the vehicle as
follows:
1. Start the engine and park the vehicle on a level
surface. Keep the engine running.
2. Apply the parking brake and place the shift lever
in P (Park).
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3. With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, move the
shift lever back to P (Park).
4. Allow the engine to idle (500 – 800 rpm) for at least
one minute. Slowly release the brake pedal.
5. Keep the engine running and press the Trip/Fuel
button or trip odometer reset stem until TRANS
TEMP (Transmission Temperature) displays on the
Driver Information Center (DIC).
6. Using the TRANS TEMP reading, determine and
perform the appropriate check procedure. If the
TRANS TEMP reading is not within the required
temperature ranges, allow the vehicle to cool,
or operate the vehicle until the appropriate
transmission uid temperature is reached.Cold Check Procedure
Use this procedure only as a reference to determine if
the transmission has enough uid to be operated
safely until a hot check procedure can be made. The
hot check procedure is the most accurate method
to check the uid level. Perform the hot check procedure
at the rst opportunity. Use this cold check procedure
to check uid level when the transmission temperature is
between 80°F and 90°F (27°C and 32°C).
1. Locate the transmission
dipstick at the
rear of the engine
compartment, on the
passenger side of the
vehicle.
SeeEngine Compartment Overview on page 5-14
for more information.
2. Flip the handle up, and then pull out the dipstick
and wipe it with a clean rag or paper towel.
3. Install the dipstick by pushing it back in all the way,
wait three seconds, and then pull it back out again.
4. Check both sides of the dipstick and read the lower
level. Repeat the check procedure to verify the
reading.
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5. If the uid level is below the COLD check band,
add only enough uid as necessary to bring the
level into the COLD band. It does not take
much uid, generally less than one pint (0.5L).
Do not overll.
6. Perform a hot check at the rst opportunity after
the transmission reaches a normal operating
temperature between 160°F to 200°F (71°C to 93°C).
7. If the uid level is in the acceptable range, push the
dipstick back in all the way, then ip the handle
down to lock the dipstick in place.
Hot Check Procedure
Use this procedure to check the transmission uid level
when the transmission uid temperature is between
160°F and 200°F (71°C and 93°C).
The hot check is the most accurate method to check the
uid level. The hot check should be performed at the rst
opportunity in order to verify the cold check. The uid
level rises as uid temperature increases, so it is
important to ensure the transmission temperature is
within range.
1. Locate the transmission
dipstick at the
rear of the engine
compartment, on the
passenger side of
the vehicle.
SeeEngine Compartment Overview on page 5-14
for more information.
2. Flip the handle up, and then pull out the dipstick
and wipe it with a clean rag or paper towel.
3. Install the dipstick by pushing it back in all the way,
wait three seconds, and then pull it back out again.
4. Check both sides of the dipstick and read the lower
level. Repeat the check procedure to verify the
reading.
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