1998 PONTIAC GRAND PRIX cooling

If you drive regularly in steep country, or if you’re
planning to visit there, here are some
tips that can make
your trips safer and more enjoyable.
Keep your vehicle in good shape. Check all fluid
levels and
also the brakes, tires, cooling system
and transaxle. These parts can work hard on
mountain roads.
Know how to go down hills. The most important
thing to know is
this: let your engine do some of the
slowing down. Shift to a lower gear when you go
down a steep or long hill.
A
/I CAUTION:
If you don’t shift down, your brakes could
get
so hot that they wouldn’t work well. You
would then have poor braking or even none going
down
a hill. You could crash. Shift down to let
your engine
assist your brakes on a steep
downhill slope.
I /I CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition
off is dangerous. Your brakes will have to
do all the work of slowing down. They could get so
hot that they wouldn’t work well. You would then
have
poor braking or even none going down a hill.
You could crash. Always have your engine running
and your vehicle in gear when you go downhill.
e
e
e
e
Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and
transaxle, and you can climb the hill better.
Stay
in your own lane when driving on two-lane
roads in hills
or mountains. Don’t swing wide or cut
across the center
of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could be
something in your lane, like a stalled car or an accident.
You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area or winding
roads. Be alert to these and take appropriate action.
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When You Are Ready to Leave After
Parking on
a Hill
1. Apply your regular brakes and hold the pedal down
while you:
0 Start your engine;
0 Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on
this. Things that are especially important in trailer
operation are automatic transaxle fluid (don’t overfill),
engine oil,
drive belts, cooling system and brake
adjustment. Each
of these is covered in this manual, and
the Index will help you find them quickly. If you’re
trailering, it’s a good idea to review
this information
before you
start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. See “Engine Overheating”
in the Index.
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Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
3100 Engine
3800 and 3800 Supercharged Engine
A. Coolant Recovery Tank
B. Electric Engine Cooling Fans
C. Radiator Pressure Cap
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’ A 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 coolant level should be at or above the COLD mark
on the overflow hose
in the coolant recovery tank. To
check the coolant level, remove the cap on the coolant
recovery tank. Check to make sure that the coolant level
is up to the COLD fill level on the hose attached to
the cap.
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.
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I A CAUTION: I
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 fined before you drive the vehicle.
NOTICE:
Engine damage if you keep running your engine
without coolant isn’t covered by your warranty.
See “Overheated Engine Protection Operating
Mode” in the Index.
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.
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 of clean
wuter (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.
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I 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
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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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.
How to Add Coolant to the Radiator
NOTICE:
Your engine has a specific radiator fill procedure.
Failure to
follow this procedure could cause your
engine to overheat and be severely damaged.
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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 fist
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.
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.
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