2007 CHEVROLET COBALT engine coolant

Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the coolant surge
tank, but only when the engine is cool. If the coolant
surge tank is empty, a special ll procedure is
necessary. SeeEngine Overheating on page 309
for instructions on “How to Add Coolant to the
Coolant Surge Tank.”
{CAUTION:
You can be burned if you spill coolant
on hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not
spill coolant on a hot engine.
When replacing the pressure cap, make sure it
is hand-tight and fully seated.
305

Checking Intercooler System Coolant
(2.0L L4 Supercharged Engine Only)
The intercooler system ll neck is located in the
front of the engine compartment, near the center of
the vehicle. SeeEngine Compartment Overview
on page 290for more information on location.
{CAUTION:
Turning the ll neck pressure cap when
the engine and intercooler are hot can
allow steam and scalding liquids to blow
out and burn you badly. Never turn the ll
neck pressure cap — even a little — when
the engine and intercooler are hot.
Park your vehicle on a level surface and turn off the
engine. When the engine is cold, the coolant level
should be visible within the horizontal tube section
of the ll neck. When the engine is warm, the
coolant level could be as high as the FULL HOT line
on the ll neck, or a little higher.
306

Adding Coolant to the Intercooler System
Fill Neck
If coolant is not visible in the ll neck, add a 50/50
mixture of clean, drinkable water and DEX-COOL®
coolant at the ll neck, but be sure that the
cooling system, including the ll neck pressure
cap, is cool before you do so.
{CAUTION:
Steam and scalding liquids from a hot
cooling system can blow out and burn
you badly. They are under pressure, and if
you turn the intercooler system pressure
cap — even a little — they can come out
at high speed. Never turn the cap when
the intercooler system, including the
intercooler system pressure cap, is hot.
Wait for the intercooler system and
intercooler system pressure cap to cool
if you ever have to turn the pressure cap.
{CAUTION:
Adding only plain water to your
intercooler system can be dangerous.
Plain water, or some other liquid such as
alcohol, can boil before the proper coolant
mixture will. With plain water or the wrong
mixture, your engine could get too hot.
Your engine could catch re and you or
others could be burned. Use a 50/50
mixture of clean, drinkable water and
DEX-COOL
®coolant.
Notice:In cold weather, water can freeze
and crack the engine, intercooler, and other
parts. Use the recommended coolant and
the proper coolant mixture.
307

{CAUTION:
You can be burned if you spill coolant
on hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
1. You can remove the ll neck pressure cap
when the intercooler system, including the
upper intercooler hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
about one-quarter of a turn. If you hear a
hiss, wait for that to stop. This will allow any
remaining pressure to be vented.
2. Then keep turning the pressure cap slowly,
and remove it.3. Add the proper DEX-COOL
®coolant mixture
to the ll neck, until there is coolant visible in
the horizontal tube section of the ll neck.
4. With the ll neck pressure cap off, start the
engine and let it run for at least 30 seconds.
Watch out for the engine cooling fan. Turn the
engine off. By this time, the coolant level inside
the ll neck may be lower. If the level drops so
that coolant is no longer visible in the horizontal
tube section of the ll neck, add more of the
DEX-COOL
®coolant mixture to the ll neck
until the level is again visible in the horizontal
tube section.
5. Replace the intercooler system pressure cap.
Be sure the pressure cap is hand-tight and
fully seated.
If the coolant is not at the proper level when
the system cools down again, see your dealer.
308

Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 290for more
information on location.
Engine Overheating
You will nd an engine coolant temperature
warning light on your vehicle’s instrument panel.
SeeEngine Coolant Temperature Warning
Light on page 174for more information.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Just
turn it off and get everyone away from
the vehicle until it cools down. Wait until
there is no sign of steam or coolant
before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re.
You or others could be badly burned.
Stop your engine if it overheats, and get
out of the vehicle until the engine is cool.
Notice:If your engine catches re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
309

If No Steam Is Coming From
Your Engine
An engine coolant temperature warning can
indicate a serious problem. SeeEngine Coolant
Temperature Warning Light on page 174.
If you get an engine coolant temperature warning,
but see or hear no steam, the problem may not
be too serious. Sometimes the engine can
get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.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) for automatic transaxle
or NEUTRAL for manual transaxle, 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.
310

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
311

A. Electric Engine Cooling Fans
B. Intercooler System Pressure Cap
C. Coolant Surge Tank and Pressure Cap
{CAUTION:
An electric engine cooling fan under the
hood can start up even when the engine
is not running and can injure you. Keep
hands, clothing, and tools away from any
underhood electric fan.
If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.
The coolant level should be at the COLD FILL line.
If it is not, you may have a leak at the pressure cap
or in the radiator hoses, heater hoses, radiator,
water pump, or somewhere in the cooling system.
{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
CAUTION: (Continued)
2.0L L4 Supercharged Engine
312