2003 CHEVROLET ASTRO CARGO VAN heater

If No Steam Is Coming From Your
Engine
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. See²Driving on Gradesº inTowing a
Trailer on page 4-31
.
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,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window 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 doesn't 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's still no sign of steam, you can push down the
accelerator until the engine speed is about twice as fast
as normal idle speed for at least three minutes while
you're parked. If you still have the warning,
turn off the
engine and get everyone out of the vehicleuntil it
cools down.
You may decide not to lift the hood but to get service
help right away.
5-32

Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Cooling Fan
If the coolant inside the coolant recovery tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface.The coolant level should
be at the ADD mark.
If it isn't, 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. Don't touch them. If you
do, you can be burned.
Don't 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.
5-33

If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn't, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant isn't covered by your warranty.
Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50 000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
How to Add Coolant to the Coolant
Recovery Tank
If you haven't found a problem yet, but the coolant level
isn't at the ADD mark, add a 50/50 mixture ofclean
drinkable water, and DEX-COOLžengine coolant at the
coolant recovery tank. SeeEngine Coolant on
page 5-28for more information.
{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 wouldn't 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
žcoolant.
5-34

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. Don't spill coolant on a hot engine.
When the coolant in the coolant recovery tank is at the
ADD mark, start your vehicle.
5-35

Relays Usage
A/C Relay
(Rear Heat and
A/C)Rear/Heat and Air Conditioning
Up®tter-ACCY
RelayUp®tter Accessory
Starter Enable
RelayStarter
A/C Enable
RelayAir Conditioning
Headlamps
RelayHeadlamps
Fuel Pump
RelayFuel Pump
Fuse/Circuit
BreakerUsage
UPFITTER-BATTUp®tter Battery Power Stud, Trailer
Wiring Harness
UPFITTER-ACCY Up®tter Accessory Relay
Spare Not used
Spare Not used
Spare Not usedFuse/Circuit
BreakerUsage
ECM-1BFuel Pump Relay and Motor, VCM,
Oil Pressure Switch/Sender
HORN Horn Relay and Horn
A/C COMPAir Conditioning Enable Relay and
Compressor
RR HTR/AC Rear Heater and Air Conditioning
ATC Active Transfer Case-L Van
FRT HVAC Front Heater and Air Conditioning
ENG-IOxygen Sensors, Camshaft Position
Sensor, Mass Air Flow Sensor,
Evaporative Emission Canister Vent
Solenoid
IGN-E Air Conditioning Enable Relay Coil
ECM-IFuel Injectors 1±6, Crankshaft
Position Sensot, VCM, Coil Driver
Module (EST), Ignition Coil
Blank Not Used
RH HDLMP Right Headlamp
LH Headlamp Left Headlamp
Blank Not Used
Blank Not Used
5-97

Capacities and Speci®cations
Please refer toPart D: Recommended Fluids and Lubricants on page 6-32for more information. See refrigerant
charge label under the hood for charge capacity information and requirements.
Engine Speci®cations
Engine RPO Transmission Spark Plug Gap Firing OrderWheel Nut
Torque
ªVortecº 4300 V6 MFI* LU3 M300.060 inches
(1.52 mm)1±6±5±4±3±2140 lb ft
190Y
*Micro Fuel InjectionTire Pressures ± See
Loading Your Vehicle on page 4-29.
Capacities and Speci®cations
ApplicationCapacities
English Metric
Cooling Capacities
Quantity without Rear Heater
Quantity with Rear Heater13.5 quarts
16.5 quarts12.8 L
15.6 L
Engine Oil with Filter 4.5 quarts 4.3 L
Fuel Tank 27.0 gallons 101.8 L
Transmission Fluid (Drain and Re®ll) 5.0 quarts 4.7 L
5-99

Checking Brake Fluid......................................5-43
Checking Coolant............................................5-29
Checking Engine Oil........................................5-15
Checking Things Under the Hood......................5-11
Checking Your Restraint Systems......................1-71
Check...........................................................3-30
Engine Light...............................................3-30
Gages Warning Light...................................3-36
Chemical Paint Spotting...................................5-89
Child Restraints..............................................1-44
Child Restraint Systems...............................1-44
Infants and Young Children...........................1-38
Lower Anchorages and Top Tethers for
Children (LATCH System)..........................1-52
Older Children.............................................1-35
Securing a Child Restraint Designed for the
LATCH System........................................1-54
Securing a Child Restraint in a Center Seat
Position..................................................1-57
Securing a Child Restraint in a Rear Outside
Seat Position...........................................1-54
Securing a Child Restraint in the Right Front
Seat Position...........................................1-59
Top Strap Anchor Location............................1-50
Top Strap...................................................1-48
Where to Put the Restraint...........................1-47
Cigarette Lighter.............................................3-17
Cleaning Aluminum Wheels..............................5-88
Cleaning Exterior Lamps/Lenses.......................5-86Cleaning Fabric/Carpet....................................5-83
Cleaning Glass Surfaces..................................5-85
Cleaning Interior Plastic Components.................5-85
Cleaning Leather............................................5-85
Cleaning the Top of the Instrument Panel...........5-85
Cleaning the Windshield and Wiper Blades.........5-87
Cleaning Tires................................................5-88
Cleaning Vinyl................................................5-85
Cleaning........................................................5-83
Inside of Your Vehicle..................................5-83
Outside of Your Vehicle................................5-86
Underbody Maintenance...............................5-89
Weatherstrips..............................................5-86
Climate Control System...................................3-18
Rear Air Conditioning System........................3-20
Rear Heating System...................................3-19
Rear..........................................................3-21
Compact Disc Messages..................................3-45
Compact Spare Tire........................................5-82
Composite Headlamps.....................................5-56
Control of a Vehicle.......................................... 4-6
Convenience Net............................................2-45
Coolant.........................................................3-30
Engine Temperature Gage............................3-30
Heater, Engine............................................2-22
Cooling System..............................................5-33
Cruise Control................................................3-10
Current and Past Model Order Forms................7-12
3

Electrical System (cont.)
Power Windows and Other Power Options......5-92
Windshield Wiper Fuses...............................5-92
Emissions Inspection and Maintenance
Programs...................................................3-33
Engine Coolant Level Check.............................6-26
Engine Oil Additives........................................5-18
Engine Oil Level Check...................................6-26
Engine..........................................................5-24
Air Cleaner/Filter.........................................5-24
Battery.......................................................5-46
Check and Service Engine Soon Light............3-30
Compartment Overview................................5-14
Coolant Heater............................................2-22
Coolant Temperature Gage...........................3-30
Coolant......................................................5-28
Cooling System Inspection............................6-30
Cover........................................................5-20
Exhaust.....................................................2-30
Fan Noise..................................................5-39
Oil .............................................................5-15
Overheating................................................5-31
Starting......................................................2-21
Entry Lighting.................................................3-15
Erasing HomeLink
žButtons..............................2-37
Except Cargo Vans.................................1-38, 1-47
Exit Lighting...................................................3-15Express-Down Window....................................2-17
Extender, Safety Belt.......................................1-34
Exterior Lamps...............................................3-12
F
Filter.............................................................5-24
Engine Air Cleaner......................................5-24
Finding a Station....................................3-39, 3-41
Finish Care....................................................5-87
Finish Damage...............................................5-88
Fixed Mast Antenna........................................3-50
Flash-to-Pass................................................... 3-7
Flat Tire, Changing.........................................5-71
Flat Tire........................................................5-70
Fluid.............................................................5-25
Automatic Transmission................................5-25
Power Steering...........................................5-40
Windshield Washer......................................5-41
FM ...............................................................3-50
Following Distance..........................................4-38
Front Axle......................................................5-54
Front Doors..................................................... 2-8
Fuel Regulator................................................2-21
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
5