2003 BUICK CENTURY engine

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 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 vehicleuntil it cools down. Also, see
ªOverheated Engine Protection Operating Modeº listed
previously in this section.
You may decide not to lift the hood but to get service
help right away.
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Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
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.
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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.
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.
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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 COLD mark, add a 50/50 mixture ofclean,
drinkable waterand DEX-COOLžengine coolant at
the coolant recovery tank. SeeEngine Coolant on
page 5-23for 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.
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
COLD mark, start your vehicle.
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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.
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 ®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.
2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.
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{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. After the engine cools, open the coolant air bleed
valves.
There are two bleed valves. One is located on the
thermostat housing. The other is located on the
thermostat bypass tube.4. Fill the radiator with the
proper DEX-COOL
ž
coolant mixture,
up to the base of the
®ller neck. See
Engine Coolant on
page 5-23for more
information about the
proper coolant mixture.
If you see a stream of coolant coming from an air
bleed valve, close the valve. Otherwise, close
the valves after the radiator is ®lled.
5. Rinse or wipe any spilled coolant from the engine
and the compartment.
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6. Then ®ll the coolant recovery tank to the COLD
mark on the coolant recovery tank.
7. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap off.8. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.
9. By this time, the coolant level inside the radiator
®ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
žcoolant mixture
through the ®ller neck until the level reaches
the base of the ®ller neck.
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10. Then replace the pressure cap. At any time during
this procedure if coolant begins to ¯ow out of the
®ller neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up like this.
11. Check the coolant in the recovery tank. The level in
the coolant recovery tank should be at the HOT
mark when the engine is hot or at the COLD mark
when the engine is cold.
Power Steering Fluid
The power steering ¯uid reservoir is located on the
passenger's side of the vehicle at the back of the engine
compartment, and can be identi®ed by the above
graphic on the cap. See
Engine Compartment Overview
on page 5-12for reservoir location.
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