2006 PONTIAC GTO engine overheat

The level should never read over the HOT mark, so be
careful not to add too much. It does not take much
¯uid, generally less than 0.6 pints (0.3 L). Do not over®ll.
Notice:Use of the incorrect automatic transmission
¯uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission ¯uid listed in
Recommended Fluids and Lubricants on page 6-12.
·After adding ¯uid, recheck the ¯uid level as
described under ªHow to Check Automatic
Transmission Fluid,º earlier in this section.
·When the correct ¯uid level is obtained, push the
dipstick back in all the way.
Remember to always replace the dipstick and lock
the handle down.
·If ¯uid has to be added often, there may be a
problem or leak and you should see your dealer.
Manual Transmission Fluid
When to Check Manual Transmission
Fluid
A good time to have your manual transmission ¯uid
checked is when the engine oil is changed. However,
the ¯uid in your manual transmission does not
require changing.
How to Check Manual Transmission
Fluid
Because this operation can be difficult, you may choose
to have this done at the dealership service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading.
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
part 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.
Check the ¯uid level only when your engine is off, the
vehicle is parked on a level place, and the transmission
is cool enough for you to rest your ®ngers on the
transmission case.
Then, follow these steps:
1. Remove the reverse light switch.
2. Check that the lubricant level is up to the bottom of
the switch hole.
3. If the ¯uid level is good, install the switch and be
sure it is fully seated. If the ¯uid level is low, add
more ¯uid as described in the next steps.
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How to Check and Add Fluid
To check the ¯uid level, look at the markings on the
reservoir. If the ¯uid level is between the MIN and the
MAX line, the ¯uid level is correct. If the ¯uid level
is between these marks do not remove the cap, as the
¯uid will quickly absorb moisture. See
Engine
Compartment Overview on page 5-12for more
information on reservoir location.
If ¯uid does need to be added, ®rst turn the vehicle off.
Remove the cap and add the proper ¯uid. Remember
to replace the cap and clean up any spilled ¯uid.
Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in the vehicle for ®ve years or 150,000 miles
(240 000 km), whichever occurs ®rst, if only
DEX-COOL
žextended life coolant is added.The following explains the cooling system and how to
add coolant when it is low. If there is a problem
with engine overheating or if coolant needs to be added
to the radiator, see
Engine Overheating on page 5-26.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
žcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·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-COOLžmay
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
ž(silicate-free) coolant in your vehicle.
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What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOLžcoolant which will not damage
aluminum parts. If this coolant mixture is used, nothing
else needs to be added.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
žcoolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.If coolant needs to be added more than four times a
year, have your dealer check the cooling system.
Notice:If you use extra inhibitors and/or additives
in your vehicle's cooling system, you could
damage your vehicle. Use only the proper mixture
of the engine coolant listed in this manual for
the cooling system. See
Recommended Fluids and
Lubricants on page 6-12for more information.
Checking Coolant
The coolant over¯ow reservoir is located in the engine
compartment on the driver's side of the vehicle. See
Engine Compartment Overview on page 5-12for more
information on location.
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If the coolant over¯ow reservoir is completely empty,
add coolant to the radiator. SeeEngine Overheating on
page 5-26.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the
radiator. Never turn the radiator pressure
cap Ð even a little Ð when the engine and
radiator are hot.
Occasionally check the coolant in the radiator. For
information on how to add coolant to the radiator, see
Cooling System on page 5-29.
Radiator 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.
See
Engine Compartment Overview on page 5-12for
information on location.
Engine Overheating
Immediate action is required if your engine overheats.
This is indicated by the coolant temperature gage
and the Engine Temp Hot message on the trip computer
display. See
Engine Coolant Temperature Gage on
page 3-28andTrip Computer on page 3-33for more
information.
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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.
If No Steam Is Coming From Your
Engine
An overheat warning, along with an Engine Temp Hot
message can indicate a serious problem.
If you get an engine overheat 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.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
apply the parking brake, shift to PARK (P) or
NEUTRAL (N) and let the engine idle while you get
out and check that the cooling fan is working.
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2. If the fan is working and the temperature gage
needle has not returned to its normal position
within a few minutes, stop the engine and remove
the ignition key.
Look for leaks at the radiator hoses and
connections, heater hoses and connections,
radiator, and water pump. Be careful when checking
these areas as they will probably still be hot. If
you ®nd a major leak or other problems that may
have caused the engine to overheat, do not run the
engine until these problems have been corrected.
If you do not ®nd anything wrong, you should check
the engine coolant level. See
Engine Coolant on
page 5-23. You should also check the air intake
area below the front bumper to ensure that it is clear
of leaves and road grime.3. Turn off your air conditioning and 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.
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The coolant level should be at or above the bottom
arrow on the dipstick. 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 else 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.
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 ®re, and you could be
burned. Get any leak ®xed 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:If you operate the engine without coolant
or fail to maintain the cooling system properly,
you could damage the engine. The repairs would not
be covered by your warranty. Always follow the
maintenance schedule in this manual for
maintaining your cooling system. See
Cooling
System on page 5-29for more information.
Notice:Using coolant other than DEX-COOLžmay
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 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
ž(silicate-free) coolant in your vehicle.
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How to Add Coolant to the Coolant
Over¯ow Reservoir
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
žcoolant.If you have not found a problem yet, check the coolant
level on the coolant over¯ow reservoir dipstick. If
the coolant level is not at or above the bottom arrow on
the dipstick, add a 50/50 mixture of clean, drinkable
water and DEX-COOL
žcoolant at the coolant over¯ow
reservoir. SeeEngine Coolant on page 5-23for
more information.
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.
{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.
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