2003 PONTIAC GRAND PRIX engine overheat

Engine Coolant Heater

Your vehicle may be equipped with an engine coolant
heater. In very cold weather,
0°F (-18°C) or colder,
the engine coolant heater can help. You’ll get easier
starting and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior
to starting your vehicle.
At temperatures above 32°F
(OOC), use of the coolant
heater
is not required.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located below the engine air
cleaner/filter near the coolant reservoir bottle. See
Engine Comparfment Overview on page
5-12
for more information on location.
3. Plug
it into a normal, grounded 1 IO-volt AC outlet.
Plugging the cord into an ungrounded outlet
could cause an electrical shock.
Also, the
wrong kind of extension cord could overheat
and cause a fire. You could be seriously injured. Plug the cord into a properly grounded
three-prong 110-volt
AC outlet. If the cord
won’t reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before
to keep it away
from moving engine parts. If you don’t, it could be
damaged.
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You’ll shift down to the next gear and have more power.
Notice: If your vehicle seems to start up rather
slowly, or if
it seems not to shift gears as you go
faster, something may be wrong with a transaxle system sensor.
If you drive very far that way, your
vehicle can be damaged. So, if
this happens,
have your vehicle serviced right away. Until then,
you can use SECOND
(2) when you are driving
less than
35 mph (55 km/h) and AUTOMATIC
OVERDRIVE (D) for higher speeds.
THIRD
(3): This position is also used for normal driving,
but
it offers more power and lower fuel economy than
AUTOMATIC OVERDRIVE
(@ ).
Here are some times you might choose THIRD (3)
instead of AUTOMATIC OVERDRIVE (a):
When driving on hilly, winding roads.
When towing a trailer, so there is less shifting
between gears.
When going down a steep hill.
When driving in non-highway scenarios
(i.e. city streets, etc.). SECOND
(2): This
position gives you more power but
lower fuel economy than THIRD
(3). You can use
SECOND (2) on hills. It can help control your speed as
you go down steep mountain roads, but then you
would also want to use your brakes
off and on.
Notice: Don’t drive in SECOND (2) for more than
25 miles (40 km), or at speeds over 55 mph
(90 km/h), or you can damage your transaxle.
Use THIRD
(3) or AUTOMATIC OVERDRIVE (D) as
much as possible. Don’t shift into SECOND
(2)
unless you are going slower than 65 mph (105 km/h)
or you can damage your engine.
FIRST
(1): This position gives you even more power
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is in
FIRST (I), the transaxle won’t shift into
first gear until the vehicle is going slowly enough.
Notice: If your front wheels won’t turn, don’t try to
drive. This might happen if you were stuck in
very deep sand or mud or were up against a solid
object. You could damage your transaxle. Also,
if you stop when going uphill, don’t hold your
vehicle there with only the accelerator pedal. This
could overheat and damage the transaxle. Use your
brakes to hold your vehicle in position on
a hill.
2-26

Leaving Your Vehicle With the Engine
Runqing
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever
is not fully in
PARK (P) with the parking brake firmly set.
And, if you leave the vehicle with the engine
running, it could overheat and even catch fire.
You or others could be injured. Don’t leave
your vehicle with the engine running.
If you have to leave your vehicle with the engine
running, be sure the vehicle
is in PARK (P) and the
parking brake is firmly set before you leave it. After
you’ve moved the shift lever into PARK (P), hold the
regular brake pedal down. Then, see if you can
move the shift lever away from PARK (P) (without first
pushing the shift lever button).
If you can, it means
that the shift lever wasn’t fully locked into PARK (P).
Torque Lock
If you are parking on a hill and you don’t shift your
transaxle into PARK (P) properly, the weight of
the vehicle may put too much force on the parking pawl
in the transaxle. You may find it difficult to pull the
shift lever out of PARK (P). This is called “torque lock”.
To prevent torque lock, set the parking brake and
then shift into PARK (P) properly before you leave the
driver’s seat.
To find out how, see Shifting Into Park (P)
on page 2-28.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transaxle,
so you
can pull the shift lever out of PARK
(P).
2-29

Anti-Lock Brake System Warning Light
if your vehicle has the
optional anti-lock brake
system, this light will come
on when your engine is
started and may stay on
for several seconds.
That’s normal.
If the anti-lock brake system warning light stays on
longer than normal after you’ve started your engine, turn
the ignition
off. If the light comes on and stays on
while you’re driving, stop as soon as possible and turn
the ignition
off. Then start the engine again to reset
the system.
If the light still stays on, or comes on again
while you’re driving, your vehicle needs service.
If
the light is on and the regular brake system warning
light isn’t on, you still have brakes, but you don’t have
anti-lock brakes.
The anti-lock brake system warning light should come
on briefly when you turn the ignition key to
RUN. This is
normal.
If the light doesn’t come on then, have it
fixed
so it will be ready to warn you if there is a problem.
Traction Control System (TCS)
Warning Light
TCS
OFF
If your vehicle is
equipped with the 3800
supercharged V6 engine,
the traction control
system warning light
may come on for the
following reasons:
If you turn the system off by pressing the TCS
button located on the far right side of the trip
computer, the warning light will come on and stay
on. To turn the system back on, press the button
again. The warning light should go
off. See Traction
Control System (TCS) on page
4-10 for more
information.
@ If there’s a brake system problem that is specifically
related to traction control, the traction control
system will turn
off and the warning light will come
on. If your brakes begin to overheat, the traction
control system will turn
off and the warning light will
come on until your brakes cool down.
If the traction control system warning light comes on
and stays on for an extended period of time when the
system
is turned on, your vehicle needs service.
3-29

Engine Coolant Temperature
Warning Light
TEMP
This light tells goti ihai
the engine coolant has
overheated or the
radiator cooling fan is
not working.
If you have been operating the vehicle under normal
driving conditions, you should pull
of the road, stop the
vehicle and turn
off the engine as soon as possible.
See Engine Overheating on page
5-33.
Engine Coolant Temperature Gage
United States
19
Canada
Your vehicle has a gage that shows the engine coolant
temperature.
If the gage pointer moves into the
shaded area, the engine is too hot.
That reading means the same thing as the warning
light. It means that the engine coolant has overheated.
If you have been operating the vehicle under normal
conditions, you should pull
off the road, stop the vehicle,
and turn
off the engine as soon as possible.
See Engine Overheating
on page 5-33.
3-31

If You Are Stuck: In Sand, Mud,
Ice or Snow
In order to free your vehicle when it is stuck, you will
need
to spin the wheels, but you don’t want 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.
If yo
et your tires s 1 ai -. spee--7 ~~~ -y 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.
Notice: Spinning your wheels can destroy parts of
your vehicle as well as the
tires. If you spin the
wheels too fast while shifting your transaxle back
and forth, you can destroy your transaxle. See
“Rocking Your Vehicle To Get
It Out.’’
For information about using tire chains on your vehicle,
see Tire Chains on page
5-75.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels.
If your vehicle
has traction control, you should turn the system
off.
See Traction Control System (TCS) on page 4-10. Then
shift back and forth between REVERSE (R) and a
forward gear, spinning the wheels as little as possible.
Release the accelerator pedal while you shift, and press
lightly on the accelerator pedal when the transaxl is in
gear. By slowly spinning your wheels in the forward and
reverse directions, you will cause a rocking motion
that may free your vehicle. If that doesn’t get you out
after
a few tries, you may need to be towed out. If you
do need
to be towed out, see “Towing Your Vehicle”
following.
4-32

Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle may need a
different turn signal flasher and/or extra wiring. Check
with your dealer. The arrows on your instrument
panel will flash whenever you signal a turn or lane
change. Properly hooked up, the trailer lamps will also
flash, telling other drivers you’re about to turn,
change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash for turns even
if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Your vehicle has bulb warning lights. When you plug a
trailer lighting system into your vehicle’s lighting
system, its bulb warning lights may not let you know
if
one of your lamps goes out. So, when you have a trailer
lighting system plugged in, be sure to check your
vehicle and trailer lamps from time to time to be sure
they’re all working. Once you disconnect the trailer
lamps, the bulb warning lights again can tell you
if one
of your vehicle lamps is out.
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 have to drive in
THIRD (3) instead of AUTOMATIC OVERDRIVE (D).
Parking on Hills
1 -J really should not ,,rk yo^, wG,kle, 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.
4-42

But if you ever have to park your rig on a hill, here’s
how to do it:
1.
2.
3.
4.
5.
Apply your regular brakes, but don’t shift into
PARK
(P) yet.
Have someone place chocks under the trailer
wheels.
When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
Reapply the regular brakes. Then apply your
parking brake, and then shift to PARK
(P).
Release the regular brakes.
When You Are Ready to Leave After
Parking on a
Hill
1. Apply your regular brakes and hold the pedal down
while you:
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 Part
A: Scheduled Maintenance
Services on page
6-4 for more information. Things that
are especially important in trailer operation are
automatic transaxle fluid (don’t overfill), engine oil, drive
belts, cooling system and brake system. 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
on page
5-33.
4-43