2005 CHEVROLET IMPALA engine overheat

Overheated Engine Protection
Operating Mode
This emergency operating mode allows your vehicle to
be driven to a safe place in an emergency situation.
If an overheated engine condition exists, an overheat
protection mode which alternates ring groups of
cylinders helps prevent engine damage. In this mode,
you will notice a signicant loss in power and engine
performance. The low coolant light may come on
and the temperature gage will indicate an overheat
condition exists. Driving extended miles (km) and/or
towing a trailer in the overheat protection mode should
be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil
and reset the oil life system. SeeEngine Oil
on page 5-18.
Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Engine Coolant Recovery Tank
B. Electric Engine Cooling Fans
C. Radiator Pressure Cap3400 V6 Engine
5-34

To check the coolant level, look for the COLD mark on
the side of the coolant recovery tank that faces the
engine. When the engine is cold, the coolant level
should be at or above the COLD mark on the coolant
recovery tank. 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 fans are running.
If the engine is overheating, both fans should be
running. If they are not, your vehicle needs service.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
SeeOverheated Engine Protection Operating Mode
on page 5-34for information on driving to a safe
place in an emergency.
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.
5-36

How to Add Coolant to the Coolant
Recovery Tank
If you have not found a problem yet, but the coolant
level is not at the COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®engine
coolant at the coolant recovery tank. SeeEngine
Coolant on page 5-29.
{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: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.
When the coolant in the coolant recovery tank is at the
COLD mark, start your vehicle.
5-37

If the overheat warning continues, there is one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling
system is cool before you do it.
{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
radiator pressure cap — even a little — they
can come out at high speed. Never turn the
cap when the cooling system, including the
radiator pressure cap, is hot. Wait for the
cooling system and radiator pressure cap to
cool if you ever have to turn the pressure cap.
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.
Turn the pressure cap slowly counterclockwise until
it rst 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.
5-38

Electrical System (cont.)
Power Windows and Other Power Options......5-99
Underhood Fuse Block...............................5-103
Windshield Wiper Fuses...............................5-99
Engine
Air Cleaner/Filter.........................................5-25
Battery.......................................................5-48
Change Oil Message...................................3-44
Check and Service Engine Soon Light............3-35
Coolant......................................................5-29
Coolant Heater............................................2-19
Coolant Temperature Gage...........................3-34
Engine Compartment Overview......................5-12
Exhaust.....................................................2-26
Low Oil Level Message................................3-43
Oil .............................................................5-18
Oil Life System...........................................5-21
Overheated Protection Operating Mode...........5-34
Overheating................................................5-32
Starting......................................................2-17
Supercharger Oil.........................................5-24
Entry Lighting.................................................3-17
Event Data Recorders (EDR)............................. 7-9
Extender, Safety Belt.......................................1-28
Exterior Lamps...............................................3-14F
Filter
Engine Air Cleaner......................................5-25
Finish Damage...............................................5-96
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-77
Flat Tire, Changing.........................................5-78
Flat Tire, Storing.............................................5-86
Fluid
Automatic Transaxle.....................................5-26
Power Steering...........................................5-43
Windshield Washer......................................5-44
Fog Lamps....................................................3-16
Folding Rear Seat............................................ 1-6
Front Storage Area.........................................2-36
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
Filling a Portable Fuel Container....................5-10
Filling Your Tank........................................... 5-8
Fuels in Foreign Countries.............................. 5-7
Gage.........................................................3-39
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-6
Low Warning Message.................................3-47
5

Mirrors
Automatic Dimming Rearview........................2-28
Automatic Dimming Rearview with OnStar
®.....2-29
Manual Rearview Mirror................................2-28
Manual Rearview Mirror with OnStar
®.............2-28
Outside Convex Mirror.................................2-30
Outside Power Mirrors..................................2-29
MyGMLink.com................................................ 7-3
N
New Vehicle Break-In......................................2-16
Normal Maintenance Replacement Parts............6-13
O
Odometer......................................................3-30
Odometer, Trip...............................................3-30
Off-Road Recovery..........................................4-13
Oil
Engine.......................................................5-18
Pressure Message.......................................3-42
Supercharger, Engine...................................5-24
Oil, Engine Oil Life System..............................5-21
Older Children, Restraints................................1-29
Online Owner Center........................................ 7-3OnStar
®System, see OnStar®Manual...............2-30
Other Warning Devices...................................... 3-6
Outlet Adjustment............................................3-24
Outside
Convex Mirror.............................................2-30
Power Mirrors.............................................2-29
Overheated Engine Protection Operating Mode.....5-34
Owner Checks and Services.............................. 6-9
Owners, Canadian............................................... ii
P
Parade Dimming.............................................3-18
Park (P)
Shifting Into................................................2-23
Shifting Out of............................................2-25
Parking
Brake........................................................2-22
Over Things That Burn.................................2-26
Passenger Compartment Air Filter.....................3-25
Passing.........................................................4-13
Passlock
®......................................................2-15
Power
Accessory Outlets........................................3-19
Door Locks.................................................. 2-9
Electrical System.........................................5-99
9