engine overheat PONTIAC GTO 2005 User Guide

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 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
®coolant.
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 the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant overflow 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.
5-24

If the coolant overflow 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 — even a little — 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.
SeeEngine 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. SeeEngine Coolant Temperature Gage on
page 3-28andTrip Computer on page 3-33for more
information.
5-26

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.
5-27

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 find 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 find anything wrong, you should check
the engine coolant level. SeeEngine 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.
5-28

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. SeeCooling
System on page 5-29for more information.
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 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.
5-30

How to Add Coolant to the Coolant
Overow 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
®coolant.If you have not found a problem yet, check the coolant
level on the coolant overflow 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
®coolant at the coolant overflow
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.
5-31

How to Add Coolant to the Radiator
Notice:Your engine has a specic radiator
ll procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
1. You can remove the radiator pressure cap when
the cooling system, including the radiator pressure
cap and upper radiator hose, is no longer hot.
SeeEngine Compartment Overview on page 5-12
for more information on the location of the
radiator pressure cap.
Turn the pressure cap slowly counterclockwise until
it first stops. Do not press down while turning the
pressure cap. If you hear a hiss, wait for that to stop.
A hiss means there is still some pressure left.
2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.
3. Fill the radiator with the proper DEX-COOL
®coolant
mixture, up to the base of the filler neck. See
Engine Coolant on page 5-23for more information
about the proper coolant mixture.4. Rinse or wipe any spilled coolant from the engine
and the compartment.
5. Then fill the coolant overflow reservoir to the bottom
arrow on the dipstick.
6. Put the cap back on the coolant overflow reservoir,
but leave the radiator pressure cap off.
7. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
8. By this time, the coolant level inside the radiator fill
neck may be lower. If the level is lower, add more
of the proper DEX-COOL
®coolant mixture
through the filler neck until the level reaches the
base of the filler neck.
9. Then replace the radiator pressure cap. At any time
during this procedure, if coolant begins to flow out
of the filler neck, reinstall the pressure cap. Be
sure the pressure cap is hand-tight and fully seated.
10. Check the coolant in the overflow reservoir.
The level should be at the bottom arrow on
the dipstick when the engine is cold.
See your dealer, if necessary.
5-33

Doing Your Own Service Work........................... 5-4
Dome Lamp...................................................3-16
Door
Locks.......................................................... 2-7
Programmable Automatic Door Locks............... 2-8
Driver
Position, Safety Belt.....................................1-12
Driving
At Night.....................................................4-14
City...........................................................4-18
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-19
Hill and Mountain Roads..............................4-22
In Rain and on Wet Roads...........................4-16
Racing or Other Competitive Driving...............2-18
Rocking Your Vehicle to Get it Out.................4-28
Winter........................................................4-24
E
Electrical System
Add-On Equipment......................................5-85
Engine Compartment Fuse Block...................5-88
Fuses and Circuit Breakers...........................5-86
Instrument Panel Fuse Block.........................5-86Engine
Air Cleaner/Filter.........................................5-18
Battery.......................................................5-39
Check and Service Engine Soon Light............3-28
Coolant......................................................5-23
Coolant Temperature Gage...........................3-28
Engine Compartment Overview......................5-12
Exhaust.....................................................2-26
Oil .............................................................5-13
Oil Life System...........................................5-16
Overheating................................................5-26
Racing or Other Competitive Driving...............2-18
Starting......................................................2-17
Entry Lighting.................................................3-16
Event Data Recorders (EDR)............................. 7-9
Exterior Lamps...............................................3-13
F
Filter
Engine Air Cleaner......................................5-18
Finish Damage...............................................5-82
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-68
Flat Tire, Changing.........................................5-68
Flat Tire, Storing.............................................5-75
4