2006 CHEVROLET COBALT service

Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your vehicle can
affect the airow around it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
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 5-96.
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.
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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
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 authorized GM dealer
for service.Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may 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 3-40. 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
lter must 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.
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 3-43.
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.
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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.
Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 5-12for
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 (83 000 km) interval. SeeScheduled
Maintenance on page 6-4for more information. If
you are driving in dusty/dirty conditions, inspect the lter
at each engine oil change.
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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.
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 7-14.
{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.
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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 in
Additional Required Services on page 6-6, and be
sure to use the transaxle uid listed inRecommended
Fluids and Lubricants on page 6-12.
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 in
Recommended Fluids and Lubricants on page 6-12.
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 dealership
service department and have it repaired as soon as
possible. SeeRecommended Fluids and Lubricants on
page 6-12for the proper uid to use.
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 5-38for more information.
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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 5-29.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 you get the engine coolant temperature warning with
no sign of steam, try this for a minute or so:
1. If you have an air conditioner and it is on, turn it off.
2. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
3. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
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 Cap2.2L L4 Engine shown, 2.4L L4 Engine similar
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