2006 CHEVROLET EXPRESS engine overheat

7. By this time, the coolant level inside the radiator
filler 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.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the 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.
Engine Overheating
If your vehicle has the DURAMAX Diesel engine, see
the DURAMAX Diesel manual for more information.
The vehicle has an indicator to warn of engine
overheating.
You will find an engine coolant temperature gage on
your vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 4-29for more information.You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Assistance Program on page 8-8.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
See if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal down.
If it does not, your vehicle needs service. Turn off the
engine.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:If the engine catches re because of being
driven with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered
by the vehicle warranty.
6-35

If Steam Is Coming From The Engine
Compartment
{WARNING:
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 fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine is cool.
If No Steam Is Coming From The
Engine Compartment
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too
hot when the vehicle:
•Climbs a long hill on a hot day.
•Stops after high-speed driving.
•Idles for long periods in traffic.
•Tows a trailer. See “Driving on Grades” under
Towing a Trailer on page 5-30.
If the overheat warning is displayed with no sign of
steam:
1. Turn the air off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.
6-36

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 still no sign of steam, push down the
accelerator until the engine speed is about twice
as fast as normal idle speed for at least three minutes
while you are parked. If you still have the warning,
turn off the engine until it cools down.
You may decide not to lift the hood but to get service
help right away.Engine Fan Noise
Your 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 partially disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
6-37

The vehicle has an airbag system. Before attempting
to add anything electrical to the vehicle, seeServicing
Your Airbag-Equipped Vehicle on page 2-78andAdding
Equipment to Your Airbag-Equipped Vehicle on
page 2-79.
Headlamp Wiring
The headlamp wiring is protected by fuses in the engine
compartment fuse block. An electrical overload will cause
the lamps to flicker on and off, or in some cases to remain
off. If this happens, have your headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker and a fuse. If the motor overheats due to heavy
snow, etc., the wiper will stop until the motor cools.Although the circuit is protected from electrical overload,
overload due to heavy snow, etc., may cause wiper
linkage damage. Always clear ice and heavy snow from
the windshield before using the windshield wipers. If the
overload is caused by some electrical problem and not
snow, etc., be sure to get it fixed.
Fuses and Circuit Breakers
The wiring circuits in the vehicle are protected from
short circuits by a combination of fuses and circuit
breakers. This greatly reduces the chance of fires
caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure
you replace a bad fuse with a new one of the identical
size and rating.
6-110

Engine (cont.)
Coolant Heater............................................3-25
Coolant Temperature Gage...........................4-29
Cooling System...........................................6-28
Drive Belt Routing.......................................7-15
Exhaust.....................................................3-40
Fan Noise..................................................6-37
Fast Idle System.........................................3-25
Oil .............................................................6-15
Overheating................................................6-35
Starting......................................................3-23
Engine Oil
Life System................................................6-18
Enhanced Technology Glass.............................3-19
Entry/Exit Lighting...........................................4-13
Event Data Recorders.....................................8-18
Extender, Safety Belt.......................................2-29
Exterior Lamps................................................. 4-9
F
Fast Idle System............................................3-25
Filter
Engine Air Cleaner......................................6-20
Finish Damage.............................................6-108
Fixed Mast Antenna........................................4-78
Flashers, Hazard Warning.................................. 4-3Flash-to-Pass................................................... 4-5
Flat Tire........................................................6-85
Flat Tire, Changing.........................................6-86
Flat Tire, Storing...........................................6-100
Fluid
Automatic Transmission........................6-21, 6-24
Power Steering...........................................6-38
Windshield Washer......................................6-39
Front Axle......................................................6-50
Fuel............................................................... 6-5
Additives...................................................... 6-7
California Fuel.............................................. 6-6
E85 (85% Ethanol)........................................ 6-8
Filling a Portable Fuel Container....................6-12
Filling the Tank...........................................6-10
Fuels in Foreign Countries.............................. 6-9
Gage .........................................................4-35
Gasoline Octane........................................... 6-6
Gasoline Specifications.................................. 6-6
Fuel Economy
Driving for Better.........................................1-18
Fuses
Engine Compartment Fuse Block.................6-112
Floor Console Fuse Block...........................6-111
Fuses and Circuit Breakers.........................6-110
Windshield Wiper.......................................6-110
5