2007 CHEVROLET COBALT service

Gasoline Octane
If your vehicle has the 2.2L L4 engine (VIN Code F),
use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less
than 87, you may 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, your engine needs service.
If your vehicle has the 2.4L L4 engine (VIN Code B)
or the 2.0L Supercharged engine (VIN Code P),
use premium unleaded gasoline with a posted
octane rating of 91 or higher. You may also use
regular unleaded gasoline rated at 87 octane or
higher, but your vehicle’s acceleration may
be slightly reduced, and you may notice a slight
audible knocking noise, commonly referred to
as spark knock. If the octane is less than 87,
you may notice 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.
If you are using gasoline rated at 87 octane
or higher and you hear heavy knocking, your
engine needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 284for additional information.
California Fuel
If your 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, 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 174. 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.
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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.
To help keep fuel injectors and intake valves clean,
or if your vehicle experiences problems due to
dirty injectors or valves, look for gasoline that is
advertised as TOP TIER Detergent Gasoline. Also,
your 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. General Motors
recommends that you use these gasolines if they
comply with the specications described earlier.
However, E85 (85% ethanol) and other fuels
containing more than 10% ethanol must not be
used in vehicles that were not designed for
those fuels.Notice:Your vehicle was not designed for
fuel that contains methanol. Do not use fuel
containing methanol. It can corrode metal parts
in the fuel system and also damage 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 recommends against 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 dealer for service.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be
hard to nd. Never use leaded gasoline or any other
fuel not recommended in the previous text on fuel.
Costly repairs caused by use of improper fuel would
not be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business
in the country where you will be driving.
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Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you
know 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
will be indicated can vary considerably. For the
oil life system to work properly, you must reset
the system every time the oil is changed.
When the system has calculated that oil life has
been diminished, it will indicate that an oil change
is necessary. A CHANGE OIL SOON message in
the Driver Information Center (DIC) will come on.
SeeDIC Warnings and Messages on page 184.
Change your oil as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are
driving under the best conditions, the oil life system
may not indicate that an oil change is necessary for
over a year. However, your engine oil and ltermust be changed at least once a year and at this
time the system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the system.
It is also important to check your oil regularly and
keep it at the proper level.
If the system is ever reset accidentally, you
must change your oil at 3,000 miles (5 000 km)
since your last oil change. Remember to reset the
oil life system whenever the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to
change your engine oil and lter based on vehicle
use. Anytime your oil is changed, reset the system
so it can calculate when the next oil change is
required. If a situation occurs where you change
your oil prior to a CHANGE OIL SOON message
being turned on, reset the system.
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After changing the engine oil, the system must be
reset as follows:
1. Turn the ignition to RUN, with the engine off.
2. Press the information and reset buttons
on the DIC at the same time to enter the
personalization menu. SeeDIC Vehicle
Personalization on page 186.
3. Press the information button to scroll through
the available personalization menu modes
until the DIC display shows OIL-LIFE RESET.
4. Press and hold the reset button until the DIC
display shows ACKNOWLEDGED. This will
tell you the system has been reset.
5. Turn the key to LOCK.
If the CHANGE OIL SOON message comes back
on when you start your vehicle, the engine oil
life system has not reset. Repeat the reset
procedure.What to Do with Used Oil
Used engine oil contains certain elements that may
be unhealthy for your skin and could even cause
cancer. Do not let used oil stay on your skin for
very long. Clean your skin and nails with soap and
water, or a good hand cleaner. Wash or properly
dispose of clothing or rags containing used engine
oil. See the manufacturer’s warnings about the use
and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from
the lter before disposal. Never dispose of oil by
putting it in the trash, pouring it on the ground, into
sewers, or into streams or bodies of water. Instead,
recycle it by taking it to a place that collects used
oil. If you have a problem properly disposing of
your used oil, ask your dealer, a service station,
or a local recycling center for help.
299

Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 290
for the location of the engine air cleaner/lter.
When to Inspect the Engine
Air Cleaner/Filter
Inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change
after each 50,000 mile (85 000 km) interval.
SeeScheduled Maintenance on page 396for
more information. If you are driving in dusty/dirty
conditions, inspect the lter at each engine oil
change.
How to Inspect the Engine
Air Cleaner/Filter
2.2L and 2.4L L4 Engines
To inspect the air cleaner/lter remove the lter
from the vehicle and lightly shake the lter to
release loose dust and dirt. If the lter remains
caked with dirt, a new lter is required. Never use
compressed air to clean the lter.To inspect or replace the lter, remove the screws
that hold the cover on and lift off the cover.
Be sure to reinstall the cover tightly.
2.0L L4 Supercharged Engine
There is a special procedure for inspecting and
replacing the lter. Because this procedure is
difficult, you should have it done at your dealer
service department. Contact your dealer for
additional information, or the procedure can be
found in the service manual. To purchase a service
manual, seeService Publications Ordering
Information on page 430.
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{CAUTION:
Operating the engine with the air
cleaner/lter off can cause you or others
to be burned. The air cleaner not only
cleans the air; it helps to stop ames
if the engine backres. If it is not there
and the engine backres, you could be
burned. Do not drive with it off, and be
careful working on the engine with the
air cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre
can cause a damaging engine re. And, dirt
can easily get into your engine, which will
damage it. Always have the air cleaner/lter
in place when you are driving.
Automatic Transaxle Fluid
It is not necessary to check the transaxle uid
level. A transaxle uid leak is the only reason for
uid loss. If a leak occurs, take your vehicle to
the dealership service department and have
it repaired as soon as possible.
Change the uid and lter at the intervals listed
inAdditional Required Services on page 398,
and be sure to use the transaxle uid listed in
Recommended Fluids and Lubricants on page 406.
Notice:Use of the incorrect automatic
transaxle uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transaxle uid listed inRecommended Fluids
and Lubricants on page 406.
Manual Transaxle Fluid
It is not necessary to check the transaxle uid
level. A transaxle uid leak is the only reason for
uid loss. If a leak occurs, take the vehicle to the
dealer and have it repaired as soon as possible.
SeeRecommended Fluids and Lubricants on
page 406for the proper uid to use.
301

Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self-adjusting. This system does not have its own
reservoir. It receives uid from the brake master
cylinder reservoir.
SeeBrakes on page 318for more information.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 309.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down
to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would
not be covered by your warranty. Always
use DEX-COOL
®(silicate-free) coolant in
your vehicle.
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If the warning continues and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, you can idle the
engine for three minutes while you are parked.
If you still have the warning, turn off the engine
and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get
service help right away.Cooling System
When you decide it is safe to lift the hood, here is
what you will see:
A. Electric Engine Cooling Fan
B. Coolant Surge Tank and Pressure Cap
2.2L L4 Engine shown, 2.4L L4 Engine similar
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