2006 CHEVROLET AVALANCHE engine overheat

Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed,
an overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage. In this
mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle
to be driven to a safe place in an emergency. 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. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan5.3L V8 Engine
5-32

A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan
{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. Check the coolant
level after the system cools down. Some amount of
coolant may be lost due to overheating. 8.1L V8 Engine
5-33

When the engine is cold,
the coolant level should be
at or above the FULL
COLD mark. 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.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-32for information on driving to a safe place
in an emergency.
5-34

If no coolant is visible in the surge tank, add coolant as
follows:
{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.
{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.
CAUTION: (Continued)
CAUTION: (Continued)
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.
5-36

E
Electrical System...........................................5-113
Center Instrument Panel Fuse Block.............5-116
Fuses and Circuit Breakers.........................5-113
Instrument Panel Fuse Block.......................5-114
Power Windows and Other Power Options....5-113
Underhood Fuse Block...............................5-117
Windshield Wiper Fuses.............................5-113
Engine
Air Cleaner/Filter.........................................5-23
Battery.......................................................5-44
Check and Service Engine Soon Light............3-43
Coolant......................................................5-28
Coolant Heater............................................2-31
Coolant Temperature Gage...........................3-41
Drive Belt Routing.......................................6-15
Engine Compartment Overview......................5-14
Exhaust.....................................................2-44
Fan Noise..................................................5-38
Oil .............................................................5-18
Oil Life System...........................................5-21
Overheated Protection Operating Mode...........5-32
Overheating................................................5-30
Starting......................................................2-29
Entry/Exit Lighting...........................................3-20
Event Data Recorders (EDR)............................. 7-9
Extender, Safety Belt.......................................1-28Exterior Cargo Lamps......................................3-19
Exterior Lamps...............................................3-14
F
Filter
Engine Air Cleaner......................................5-23
Finish Damage.............................................5-110
Fixed Mast Antenna.......................................3-114
Flashers, Hazard Warning.................................. 3-6
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-84
Flat Tire, Changing.........................................5-84
Flat Tire, Storing...........................................5-100
Fluid
Automatic Transmission................................5-25
Power Steering...........................................5-39
Windshield Washer......................................5-40
Fog Lamps ....................................................3-17
Four-Wheel Drive....................................2-35, 5-52
Front Armrest Storage Area..............................2-64
Front Axle......................................................5-53
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
E85 (85% Ethanol)........................................ 5-7
Filling a Portable Fuel Container....................5-11
Filling Your Tank........................................... 5-9
Fuels in Foreign Countries.............................. 5-8
5

N
Navigation/Radio System, see Navigation
Manual......................................................3-98
New Vehicle Break-In......................................2-27
Normal Maintenance Replacement Parts............6-14
O
Odometer......................................................3-33
Odometer, Trip...............................................3-33
Off-Road Driving.............................................4-17
Off-Road Recovery..........................................4-14
Oil
Engine.......................................................5-18
Pressure Gage............................................3-45
Oil, Engine Oil Life System..............................5-21
Older Children, Restraints................................1-29
Online Owner Center........................................ 7-3
OnStar
®System, see OnStar®Manual...............2-57
Other Warning Devices...................................... 3-6
Outlet Adjustment............................................3-30
Outlet(s), Accessory Power...............................3-21
Outside
Automatic Dimming Mirror with Curb
View Assist.............................................2-57
Camper-Type Mirrors....................................2-54
Convex Mirror.............................................2-56
Heated Mirrors............................................2-56Outside (cont.)
Power Mirrors.............................................2-55
Overheated Engine Protection Operating Mode . . . 5-32
Owner Checks and Services.............................. 6-9
Owners, Canadian............................................... ii
P
Paint, Damage..............................................5-110
Park (P)
Shifting Into................................................2-41
Shifting Out of............................................2-43
Parking
Brake........................................................2-40
Over Things That Burn.................................2-43
Passenger Airbag Status Indicator.....................3-35
Passenger Sensing System..............................1-63
Passing.........................................................4-14
Passlock
®......................................................2-26
Power
Accessory Outlet(s)......................................3-21
Door Locks.................................................. 2-9
Electrical System.......................................5-113
Lumbar Controls........................................... 1-3
Retained Accessory (RAP)............................2-29
Seat............................................................ 1-2
Steering Fluid.............................................5-39
Windows....................................................2-23
Programmable Automatic Door Locks.................2-10
9