engine overheat GMC SIERRA 2009 Owner's Guide

If No Steam Is Coming From The
Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, 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.
Tow a trailer. SeeTowing a Trailer on page 4-51.If you get the ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. If you are stopped in a traffic jam, apply the brake,
shift to N (Neutral); otherwise, shift to the highest
gear while driving—D(Drive) or 3 (Third).
If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer displays,
the vehicle can be driven. Continue to drive the vehicle
slow for about 10 minutes. Keep a safe vehicle distance
from the car in front of you. If the warning does not come
back on, continue to drive normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
ve minutes while parked. If the warning is still
displayed, turn off the engine until it cools down.
Also, see “Overheated Engine Protection Operating
Mode” later in this section.
5-36

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 the 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 5-15.
Engine Fan Noise
If the vehicle has a clutched engine cooling fan, when the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing, and/or
high outside temperatures, the fan speed increases as
the clutch more fully engages, so you may hear an
increase in fan noise. This is normal and should not be
mistaken as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
If the vehicle has electric cooling fans, you may hear
the fans spinning at low speed during most everyday
driving. The fans may turn off if no cooling is required.
Under heavy vehicle loading, trailer towing, and/or
high outside temperatures, or if you are operating the
air conditioning system, the fans may change to
high speed and you may hear an increase in fan noise.
This is normal and indicates that the cooling system
is functioning properly. The fans will change to low
speed when additional cooling is no longer required.
5-37

Vehicles with P265/70R17 or P275/55R20 size tires
require ination pressure adjustment when driving the
vehicle at speeds of 100 mph (160 km/h) or higher.
Set the cold tire ination pressure to 3 psi (20 kPa)
above the recommended cold tire pressure shown on
the Tire and Loading Information label.
When you end this high-speed driving, return the tires
to the cold ination pressure shown on the Tire and
Loading Information label. SeeLoading the Vehicle on
page 4-32andInflation - Tire Pressure on page 5-73.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel bolt
or wheel nut is replaced, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque and wheel nut tightening
information, seeRemoving the Spare Tire and Tools on
page 5-93.The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate the tires periodically,
seeTire Inspection and Rotation on page 5-81. Also
seeScheduled Maintenance (Gasoline Engine) on
page 6-4.
{CAUTION:
If you operate your vehicle with a tire that is badly
underinated, the tire can overheat. An overheated
tire can lose air suddenly or catch re. You or
others could be injured. Be sure all tires (including
the spare) are properly inated.
SeeInflation - Tire Pressure on page 5-73, for
information on proper tire ination.
5-75

Electrical System (cont.)
Underhood Fuse Block...............................5-126
Windshield Wiper Fuses.............................5-122
Electronic Immobilizer
PASS-Key
®III+...........................................2-20
Electronic Immobilizer Operation
PASS-Key
®III+...........................................2-20
Engine
Air Cleaner/Filter.........................................5-19
Check and Service Engine Soon Lamp...........3-45
Coolant......................................................5-29
Coolant Heater............................................2-27
Coolant Temperature Gage...........................3-44
Drive Belt Routing.......................................6-18
Engine Compartment Overview......................5-14
Exhaust.....................................................2-55
Fan Noise..................................................5-37
Fast Idle System.........................................2-25
Oil .............................................................5-15
Oil Life System...........................................5-18
Overheated Protection Operating Mode...........5-37
Overheating................................................5-34
Starting......................................................2-24
Entry Lighting.................................................3-20
Event Data Recorders.....................................7-17
Exit Lighting...................................................3-20
Extender, Safety Belt.......................................1-37
Exterior Lamps...............................................3-16
F
Fast Idle System............................................2-25
Filter
Engine Air Cleaner......................................5-19
Finish Damage.............................................5-120
Fixed Mast Antenna.......................................3-142
Flashers, Hazard Warning.................................. 3-8
Flash-to-Pass.................................................3-10
Flat Tire........................................................5-91
Flat Tire, Changing.........................................5-92
Flat Tire, Storing...........................................5-109
Fluid
Automatic Transmission........................5-21, 5-24
Power Steering...........................................5-38
Windshield Washer......................................5-39
Fog Lamp
Fog ...........................................................3-19
Fog Lamp Light..............................................3-50
Four-Wheel Drive....................................2-37, 5-51
Four-Wheel-Drive Light....................................3-51
Front Axle......................................................5-53
Fuel............................................................... 5-6
Additives...................................................... 5-7
California Fuel.............................................. 5-7
Driving for Better Economy............................. 4-2
E85 (85% Ethanol)........................................ 5-8
Filling a Portable Fuel Container....................5-12
Filling the Tank...........................................5-10
5

Mirrors (cont.)
Outside Power Mirrors..................................2-59
Outside Towing Mirrors.................................2-58
Park Tilt .....................................................2-60
MP3 ..................................................3-108, 3-113
MyGMLink.com................................................ 7-5
N
Navigation System, Privacy..............................7-18
Navigation/Radio System, see
Navigation Manual.....................................3-119
New Vehicle Break-In......................................2-22
Noise Control System, Tampering......................5-54
O
Odometer......................................................3-35
Odometer, Trip...............................................3-35
Off-Road Driving.............................................4-12
Off-Road Recovery..........................................4-10
Oil
Engine.......................................................5-15
Pressure Gage............................................3-48
Pressure Light.............................................3-49
Oil, Engine Oil Life System..............................5-18
Older Children, Restraints................................1-38
Online Owner Center........................................ 7-5
OnStar, Privacy..............................................7-18OnStar
®System, see OnStar®Manual...............2-71
Operation, Universal Home Remote System........2-75
Outlet Adjustment............................................3-33
Outlets
Accessory Power.........................................3-22
Outside
Convex Mirror.............................................2-61
Heated Mirrors............................................2-61
Manual Mirrors............................................2-58
Power Foldaway Mirrors...............................2-59
Power Mirrors.............................................2-59
Towing Mirrors............................................2-58
Overheated Engine Protection
Operating Mode..........................................5-37
Owner Checks and Services.............................6-11
Owners, Canadian............................................... ii
P
Paint, Damage..............................................5-120
Park
Shifting Into................................................2-52
Shifting Out of............................................2-54
Park Aid................................................2-62, 2-65
Park Brake....................................................2-50
Park Tilt Mirrors..............................................2-60
Parking
Assist........................................................2-62
Over Things That Burn.................................2-54
9