2010 PONTIAC G5 engine overheat

{WARNING:
Heater and radiator hoses, and other engine parts,
can be very hot. Do not touch them. If you do, you
can be burned.
Do not run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
If there seems to be no leak, with the engine on, check
to see if the electric engine cooling fan is running. If
the engine is overheating, the fan should be running. If
it is not, your vehicle needs service. Notice:
Engine damage from running the engine
without coolant is not covered by the warranty.
Notice: Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 50 000 km (30,000 miles)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in the
vehicle.
6-21

How to Add Coolant to the Coolant
Surge Tank
Notice:This vehicle has a specic coolant ll
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
If you have not found a problem yet, check to see if
coolant is visible in the coolant surge tank. If coolant is
visible but the coolant level is not at the COLD FILL
line, add a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant at the coolant surge tank, but
be sure the cooling system, including the coolant surge
tank pressure cap, is cool before you do it. See
Engine Coolant on page 6-24 for more information.
If no coolant is visible in the coolant surge tank,
add coolant as follows:
{WARNING:
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 coolant surge
tank pressure cap — even a little — they can
come out at high speed. Never turn the cap when
the cooling system, including the coolant surge
tank pressure cap, is hot. Wait for the cooling
system and coolant surge tank pressure cap to
cool if you ever have to turn the pressure cap.
6-22

{WARNING:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper coolant
mixture will. The vehicle’s coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could get
too hot but you would not get the overheat
warning. The engine could catch fire 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, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{WARNING:
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 coolant surge tank pressure cap when the cooling system, including the coolant
surge tank pressure cap and upper radiator hose, is
no longer hot. Turn the pressure cap slowly
counterclockwise about two or two and one-half
turns. If you hear a hiss, wait for that to stop. This will
let any pressure still left to be vented out the
discharge hose.
2. Then keep turning thepressure cap slowly,
and remove it.
6-23

3. Fill the coolant surge tank with the proper mixture,to the COLD FILL line. Wait about five minutes,
then check to see if the level is below the COLD
FILL line. If the level is below the line, add additional
coolant to bring the level up to the line. Repeat
this procedure until the level remains constant at the
COLD FILL line for at least five minutes.
4. With the coolant surge tank pressure cap off, start the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan. By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower than
the COLD FILL line, add more of the proper mixture
to the coolant surge tank until the level reaches
the COLD FILL line.
5. Then replace the pressure cap. Be sure the pressure cap is hand-tight and fully seated.
See your dealer/retailer, if necessary.
Engine Coolant
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first, 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, see Engine Overheating on
page 6-27.
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.
6-24

Notice:Using coolant other than DEX-COOL®can
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 the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in the
vehicle.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you do
not need to add anything else.
{WARNING:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper coolant
mixture will. The vehicle’s coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could get too
hot but would not get the overheat warning.
WARNING: (Continued)
WARNING: (Continued)
The engine could catch fire and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and other
parts.
If you have to add coolant more than four times a year,
have your dealer/retailer check your cooling system.
Notice: If extra inhibitors and/or additives are used
in the vehicle’s cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants on
page 7-10 for more information.
6-25

Checking Coolant
The coolant surge tank is located in the engine
compartment on the driver’s side of the vehicle. See
Engine Compartment Overview on page 6-12for more
information on location.
{WARNING:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids to blow out and burn you badly.
Never turn the surge tank pressure cap — even a
little — when the engine and radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the COLD
FILL line.
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 fill procedure is necessary. See Engine
Overheating on page 6-27 for instructions on “How to
Add Coolant to the Coolant Surge Tank.”
6-26

{WARNING:
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.
Engine Overheating
You will find an engine coolant temperature warning
light on your vehicle’s instrument panel. See Engine
Coolant Temperature Warning Light on page 4-29 for
more information.
If Steam Is Coming From Your Engine
{WARNING:
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 fire. 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 the engine catches re because of being
driven with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered
by the vehicle warranty.
6-27

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 4-29 .
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 N (Neutral) for automatic transmission or NEUTRAL for manual
transmission, while stopped. If it is safe to do so, pull
off the road, shift to P (Park) or N (Neutral) 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.Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer’s instructions before use. If you will be
operating your vehicle in an area where the temperature
may fall below freezing, use a fluid that has sufficient
protection against freezing.
6-28