2004 PONTIAC GRAND PRIX engine coolant

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 signi®cant loss in power and engine
performance. The engine coolant 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. See ªEngine Oilº in the Index.
If Steam Is Coming From Your Engine
{CAUTION:
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
CAUTION: (Continued)
5-30

CAUTION: (Continued)
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 ®re.
You or others could be badly burned.
Stop your engine if it overheats, and get out
of the vehicle until the engine is cool.
See ªOverheated Engine Protection Operating
Modeº in the Index for information on driving
to a safe place in an emergency.
Notice:If your engine catches ®re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not
be covered by your warranty. See ªOverheated
Engine Protection Operating Modeº in the Index
for information on driving to a safe place in an
emergency.
If No Steam is Coming From Your
Engine
An overheat warning 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.
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's 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 windows as necessary.
5-31

A. Coolant Recovery Tank
B. Electric Engine Cooling Fan
C. Radiator Pressure Cap
{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 recovery tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface.
3800 V6 Supercharged
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When the engine is cold,
the coolant level should be
at or above the COLD
mark on the coolant
recovery tank.
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.
CAUTION: (Continued)
CAUTION: (Continued)
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.
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 aren't, your vehicle needs service.
Notice:Engine damage from running your engine
without coolant isn't covered by your warranty.
See ªOverheated Engine Protection Operating
Modeº in the Index for information on driving to
a safe place in an emergency.
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.
5-34

How to Add Coolant to the Coolant
Recovery Tank
{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.
If you haven't found a problem yet, but the coolant level
isn't at the COLD mark, add a 50/50 mixture of clean,
drinkable water and DEX-COOL
žengine coolant at
the coolant recovery tank. SeeEngine Coolant on
page 5-26for more information.
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.
5-35

How to Add Coolant to the Radiator
Notice:Your engine has a speci®c radiator ®ll
procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
The radiator pressure cap is located on the passenger's
side of the vehicle in the front of the engine
compartment, near the battery and the diagonal cross
brace. See
Engine Compartment Overview on page 5-12for more information on location.You can remove the radiator pressure cap when the
cooling system, including the radiator pressure cap and
upper radiator hose, is no longer hot.
1. Turn the pressure cap slowly counterclockwise until
it ®rst stops. Don't 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.
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2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.
{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.3. If the vehicle has the 3800 V6 engine, remove the
Series III V6 engine cover shield to access the
bleed valve.
3.1. Clean the area around the engine oil ®ll tube
and cap before removing. Twist the oil ®ll
tube, with cap attached, counterclockwise
and remove it.
3800 Engine
5-38

3.2. Lift the engine cover shield at the front, slide
the catch tab out of the engine bracket and
remove the cover shield.
3.3. Put the oil ®ll tube, with cap attached, in the
valve cover oil ®ll hole until you're ready to
replace the cover shield.4. After the engine cools,
open the coolant air
bleed valve located on
the thermostat housing
near the heater hose.
3800 Supercharged Engine
Thermostat Housing
5-39