1998 PONTIAC GRAND PRIX overheating

The oil level monitoring system only checks oil level during the brief period between key on and engine
crank. It
does not monitor engine oil level when the
engine is running. Additionally, an oil level check is
only performed if the engine has been turned
off for a
considerable period of time, allowing the oil normally in
circulation to drain back into the oil pan.
Engine Coolant Temperature Light
TEMP
This light tells you that your
engine coolant has
overheated or your radiator
cooling fan
is not working.
If you have been operating your
vehicle under normal
driving conditions, you should pull
off the road, stop
your vehicle and turn
off the engine as soon as possible.
In “Problems on the Road,” this manual shows what to
do. See “Engine Overheating” in the Index.
Engine Coolant Temperature Gage
You have a gage that shows
the engine coolant
temperature. If the gage
pointer moves into
the red
area, your engine is too hot!
That reading means the sarne thing as the warning light.
It means
that your engine coolant has overheated. If you
have been operating your vehicle under normal driving
conditions, you should pull
off the road, stop your
vehicle and turn
off the engine as soon as possible.
In “Problems on the Road,”
this manual shows what to
do. See “Engine Overheating” in the Index.
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Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade.
If you don’t shift
down, you might have to use your brakes
so much that
they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your
speed to around
45 mph (70 km/h) to reduce the
possibility of engine and transaxle overheating.
If you have overdrive, you may want to drive in
THIRD (3), instead of DRIVE (D).
Parking on Hills
You really should not park your vehicle, with a trailer
attached, on a hill.
If something goes wrong, your rig
could start
to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your parking
brake, and then shift to PARK (P).
5. Release the regular brakes. PARK (P) yet.
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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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V
f Section 5 Problems on the Road
- ~~ ~~ - , I . . . . , .. - .~ . 1,F. - 1'7. -A,,. ,- , .. 5' _I ,_. . .- , ~ . .= . .-+ .. -. .. ,. .
Here you'll find what to do about some problems that can occur on the road.
5-2
5-2
5-3
5-8
5-15
Hazard Warning Flashers
Other Warning Devices
Jump Starting
Towing Your Vehicle
Engine Overheating
5 -26
5-27
5-37
5-38
If A Tire Goes Flat
Changing a Flat Tire
Compact Spare Tire
If You're Stuck: In Sand, Mud,
Ice
or Snow
5-1

Engine Overheating
You will find a coolant temperature gage and a warning
light about a hot engine on your instrument panel. See
“Engine Coolant Temperature Gage” and “Engine
Coolant Temperature Warning Light” in the Index. You
also have a low coolant light on your instrument panel.
See “Low Coolant Light” in the Index.
Overheated Engine Protection Operating
Mode
(3100 Engine Only)
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.
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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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.
5-20

How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transaxle fluid to use. See “Recommended
Fluids and Lubricants” in the Index.
If the fluid level is low, add only enough of the proper
fluid to bring the level into the cross-hatched area on
the dipstick.
1. Pull out the dipstick.
2. Using a long-neck funnel, add enough fluid at the
dipstick hole to bring it to the proper level.
It doesn’t take much fluid, generally less
than one
pint
(0.5 L). Don’t ovefill.
LOTICE:
We recommend you use only fluid labeled
DEXRON@-111, because fluid with that label
is
made especially for your automatic transaxle.
Damage caused
by fluid other than DEXRON-III
is not covered by your new vehicle warranty.
3. After adding fluid, recheck the fluid level as described
4. When the correct fluid level is obtained, push the
under “How to Check” earlier in this section.
dipstick back in
all the way.
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 km) whichever occurs first, if you add only
DEX-COOL’ extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating
or if you need to add coolant to your
radiator, see “Engine Overheating” in the Index.
A 50/50 mixture of water and DEX-COOL’
coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 OF (129°C).
J
e Protect against rust and corrosion.
e Help keep the proper engine temperature.
0 Let the warning lights and gages work as
they should.
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If this comes on, it
LOW
COOLANT
means you’re low on
engine coolant.
Adding Coolant If
you need more coolant, add the proper DEX-COOL@
coolant mixture at the coolant recovery tank, but be
careful not to spill it.
A CAUTION:
lbrning the radiator pressure cap when the
engine and radiator are hot can allow
steam and
scalding liquids to blow out and burn you badly.
With the coolant recovery tank, you will almost
never have to add coolant at the radiator.
Never turn the radiator pressure cap
-- even a
little -- when the engine and radiator are hot.
If the coolant recovery tank is completely empty, add +
coolant to the radiator. (See “Engine Overheating’’ in \
the Index.)
’ /1 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.
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