1998 OLDSMOBILE SILHOUETTE engine overheat

Engine Overheating
You will find a coolant temperature gage on your
vehicle’s instrument panel. See “Engine Coolant
Temperature Gage” in the Index. You also have a low
coolant level light on your instrument panel. See “LOW
Coolant Light” in the Index.
Overheated Engine Protection
Operating Mode
Should an overheated engine condition exist, an
overheat protection mode which alternates firing groups
of three cylinders helps prevent engine damage. In this
mode, you will notice a significant loss in power and
engine performance. The
low coolant light may come on
and the temperature gage will indicate an overheat
condition exists. This emergency operating mode allows
your vehicle to be driven to a safe place in an
emergency. Towing a trailer in the overheat protection
mode should be avoided.
1 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 and change the oil. See
“Engine Oil, When to Change” in the Index.
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If Steam Is Coming From Your Engine
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.
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. See “Overheated
Engine Protection Operating Mode” in the Index.
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If No Steam Is Coming From Your Engine
If you get the 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.
0 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. Turn off your air conditioner.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- AUTOMATIC OVERDRIVE (D)
or THIRD (3).
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, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, you can idle the engine
for two or three minutes while you’re parked, to see
if
the warning stops. But then, if you still have the
warning,
turn off the engine and get everyone out of the
vehicle
until it cools down. Also, see “Overheated
Engine Protection Operating Mode” listed previously in
this section.
You may decide not to lift the hood but to get service
help right away.
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The coolant level should be at or above the
FULL COLD mark.
If it isn’t,
you may have a leak in the radiator hoses,
heater hoses, radiator, water pump or somewhere else in
the cooling system.
’ A 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 fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
~
NOTICE:
Engine damage from running your engine
without coolant isn’t covered by your warranty.
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.
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IN:
How to Add Coolant to the Coolant
Recovery
Tank
If you haven’t found a problem yet, but the coolant
level isn’t at or above the FULL COLD mark, add a
50/50 mixture of clean water (preferably distilled) and
DEX-COOL@ engine coolant at the coolant recovery
tank.
(See “Engine Coolant” in the Index for
more information.)
- -
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like 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 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.
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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 or
above the
FULL COLD mark, start your vehicle.
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.
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~~~ ~~ ~ ~~ ~ ~ ~ NOTICE:
When
the compact spare is installed, don’t take
your vehicle through an automatic car wash with
guide rails. The compact spare can get caught on
the rails. That can damage the tire and wheel,
and maybe other parts
of your vehicle.
Don’t use your compact spare on other vehicles.
And don’t mix your compact spare tire or wheel with
other wheels or tires. They won’t fit. Keep your spare
tire and its wheel together.
NOTICE:
Tire chains won’t fit your compact spare. Using
them can damage your vehicle and can damage
the chains too. Don’t use tire chains on your
compact spare.
If You’re Stuck: In Sand, Mud,
Ice
or Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method
known as
“rocking” can help you get out when you’re stuck, but
you must use caution.
A CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transaxle
or other parts of the vehicle can
overheat. That could cause an engine
compartment fire or other damage. When you’re
stuck, spin the wheels as little as possible. Don’t
spin the wheels above
35 mph (55 km/h) as shown
on the speedometer.
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Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL engine coolant. This coolant is designed
to remain in your vehicle for
5 years or 150,000 miles
(240 000 lunb whichever occurs first, if you add only
DEX-COOL extended life coolant.
J
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see “Engine Overheating” in
the Index.
A 50/50 mixture of water and DEX-COOL@
coolant will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs
first. Damage caused by the
use of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
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