2003 PONTIAC BONNEVILLE Owners Manual

If Steam Is Coming From Your Engine
Steam from an overheated engine can ~ ~ rn
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.
Notice: If your engine catches fire because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty.
5-30

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.
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 idle the engine
for three minutes while you’re parked.
If you still
have the warning,
turn off the engine and get everyone
out
of the vehicle until it cools down.
You may decide not to lift the hood but to get service
help right away.
5-31

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. Electric Engine Cooling Fans
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.
See
Engine Compartment
Overview on page
5- 14 for
more information on
location.
5-32

The coolant level should be at or above the FULL COLD
mark when the engine is cold. The coolant level
should be at the FULL HOT mark under normal
operating conditions.
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
syster
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.
Notice: When adding coolant, it is important that
you use only
DEX-COOL@ (silicate-free) coolant.
If coolant other than
DEX-COOL is added to
the system, premature engine, heater core or
1
Heater and radiator hoses, and other engine radiator corrosion may result.
-In addition, the engine
parts, can be very hot. Don’t touch them. If you coolant will require change sooner - at 30,000 miles
(50 000 km) or 24 months, whichever occurs first.
do, you can be burned.
Damage caused by the use of coolant other
Don’t run the engine if there
is a leak. If you than DEX-COOL@ is not covered by your new vehicie
run the engine,
it could lose all coolant. That warranty.
could cause an engine fire, and you could be
burned. Get any leak fixed before you drive the
vehicle.
5-33

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 FULL COLD mark, add a
50/50 mixture of
clean, drinkable water and DEX-COOL@ engine coolant
at the coolant recovery tank. See
Engine Coolant on
page
5-26 for more information.
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 fire 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. 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
FULL
COLD mark, start your vehicle.
5-34

If the overheat warning continues, there’s one more
thing you can
try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling
system
is cool before you do it.
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.
5-35

How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when
the cooling system, including the radiator pressure
cap and upper radiator hose, is no longer hot.
Turn the pressure cap slowly counterclockwise until
it first 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.
2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.
5-36

3. Remove the 3800 Series II V6 engine cover shield
to access the bleed valve.
3.1. Clean the area around the engine oil fill tube
and cap before removing. Twist the oil
fill
tube, with cap attached, counterclockwise
and remnvc! it^
3.2. If you have the supercharged engine,
remove the nut in the center of the cover
shield.
3.3. Lift the engine cover shield at the front, slide
the catch tab out
of the engine bracket and
remove the cover shield.
3.4. Put the oil
fill tube, with cap attached, in the
valve cover oil
fill hole until you’re ready to
replace the cover shield.
4. After the engine cools,
open the coolant air
bleed valve. There
is one bleed valve. It is
located on the
thermostat housing.
5-37