2004 PONTIAC GRAND PRIX engine overheat

Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. SeePart A: Scheduled Maintenance
Services on page 6-4for more information. Things that
are especially important in trailer operation are automatic
transaxle ¯uid (don't over®ll), engine oil, drive belts,
cooling system and brake system. Each of these is
covered in this manual, and the Index will help you ®nd
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. SeeEngine Overheating
on page 5-29.
4-44

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside
of Your Vehicle...........................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Speci®cations....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Supercharger Oil..........................................5-21
Engine Air Cleaner/Filter................................5-22
Automatic Transaxle Fluid..............................5-24
Engine Coolant.............................................5-26
Radiator Pressure Cap..................................5-29
Engine Overheating.......................................5-29
Cooling System............................................5-32
Power Steering Fluid.....................................5-42
Windshield Washer Fluid................................5-43Brakes........................................................5-45
Battery........................................................5-48
Jump Starting...............................................5-49
Headlamp Aiming...........................................5-56
Bulb Replacement..........................................5-59
Halogen Bulbs..............................................5-59
Headlamps and Sidemarker Lamps.................5-60
Front Turn Signal, Parking and
Fog Lamps...............................................5-62
Center High-Mounted Stoplamp (CHMSL).........5-64
Taillamps, Turn Signal, and Stoplamps............5-64
Back-Up Lamps............................................5-65
Replacement Bulbs.......................................5-66
Windshield Wiper Blade Replacement..............5-67
Tires..............................................................5-68
In¯ation -- Tire Pressure................................5-69
Tire Pressure Monitor System.........................5-70
Tire Inspection and Rotation...........................5-71
When It Is Time for New Tires.......................5-72
Buying New Tires.........................................5-73
Uniform Tire Quality Grading..........................5-74
Wheel Alignment and Tire Balance..................5-75
Wheel Replacement......................................5-75
Tire Chains..................................................5-77
Section 5 Service and Appearance Care
5-1

Automatic Transaxle Fluid
When to Check and Change
A good time to check your automatic transaxle ¯uid
level is when the engine oil is changed.
Change both the ¯uid and ®lter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
·In heavy city traffic where the outside temperature
regularly reaches 90ÉF (32ÉC) or higher.
·In hilly or mountainous terrain.
·When doing frequent trailer towing.
·Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the ¯uid and ®lter at
100,000 miles (166 000 km).
See
Part A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little ¯uid can damage
your transaxle. Too much can mean that some of the
¯uid could come out and fall on hot engine or
exhaust system parts, starting a ®re. Too little ¯uid
could cause the transaxle to overheat. Be sure
to get an accurate reading if you check your
transaxle ¯uid.
Wait at least 30 minutes before checking the transaxle
¯uid level if you have been driving:
·When outside temperatures are above 90ÉF (32ÉC).
·At high speed for quite a while.
·In heavy traffic ± especially in hot weather.
·While pulling a trailer.
5-24

3. Check both sides of the dipstick, and read the
lower level. The ¯uid level must be in the
cross-hatched area.
4. If the ¯uid level is in the acceptable range, push the
dipstick back in all the way.
How to Add Fluid
Refer to the Maintenance Schedule to determine
what kind of transaxle ¯uid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-16.
If the ¯uid level is low, add only enough of the proper
¯uid 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 ¯uid at the
dipstick hole to bring it to the proper level.
It doesn't take much ¯uid, generally less than
one pint (0.5 L). Don't over®ll.
Notice:We recommend you use only ¯uid labeled
DEXRONž-III, because ¯uid with that label is made
especially for your automatic transaxle. Damage
caused by ¯uid other than DEXRON
ž-III is not
covered by your new vehicle warranty.
3. After adding ¯uid, recheck the ¯uid level as
described under ªHow to Checkº listed previously
in this section.
4. When the correct ¯uid level is obtained, push the
dipstick back in all the way.
Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs ®rst, if you add
only DEX-COOL
žextended 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 on page 5-29.
5-26

A 50/50 mixture of clean, drinkable water and
DEX-COOLžengine coolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·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-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 ± 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.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOLžengine coolant which won't
damage aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
{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:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
5-27

Checking Coolant
The coolant recovery tank is located in the engine
compartment toward the rear of the engine on
the passenger's side of the vehicle. See
Engine
Compartment Overview on page 5-12for more
information on location.
The vehicle must be on a level surface when checking
the coolant level.
When your engine is cold,
the coolant level should be
at the COLD mark or a
little higher.
When your engine is warm, the level should be up to
the HOT mark or a little higher.
Adding Coolant
This symbol, along with
the LOW COOLANT
LEVEL warning message
will appear in the Driver
Information Center
(DIC) when coolant needs
to be added to the
coolant recovery tank.
See
DIC Controls and Displays on page 3-45for more
information.
If you need more coolant, add the proper DEX-COOL
ž
coolant mixture at the coolant recovery tank, but be
careful not to spill it.
If the coolant recovery tank is completely empty,
add coolant to the radiator. See
Engine Overheating on
page 5-29.
5-28

{CAUTION:
Turning 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.
{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.
Occasionally check the coolant level in the radiator.
For information on how to add coolant to the radiator,
see
Cooling System on page 5-32.
Radiator Pressure Cap
Notice:Your radiator cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
Be sure the arrows on the cap line up with the
over¯ow tube on the radiator ®ller neck.
The radiator pressure cap is located in the front of the
engine compartment on the passenger's side, near
the diagonal cross brace. See
Engine Compartment
Overview on page 5-12for more information on location.
Engine Overheating
You will ®nd a coolant temperature gage and a warning
light concerning an overheated engine condition on
the instrument panel cluster. See
Engine Coolant
Temperature Gage on page 3-39andEngine Coolant
Temperature Warning Light on page 3-39.
5-29

Overheated Engine Protection
Operating Mode
This emergency operating mode allows your vehicle to
be driven to a safe place in an emergency situation.
If an overheated engine condition exists, an overheat
protection mode which alternates ®ring groups of
cylinders helps prevent engine damage. In this mode,
you will notice a signi®cant loss in power and engine
performance. The engine coolant temperature gage will
indicate an overheat condition exists. Driving extended
miles (km) and/or 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, change the oil and reset the oil
life system. See ªEngine Oilº in the Index.
If Steam Is Coming From Your Engine
{CAUTION:
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
CAUTION: (Continued)
5-30