2003 FORD MUSTANG engine overheat

4. Inspect for normal burning.
zCheck for light tan or gray deposits on the firing tip.
5. Inspect for pre- ignition, identified by melted electrodes and a possibly damaged insulator.
Metallic deposits on the insulator indicate engine damage. This may be caused by incorrect
ignition timing, wrong type of fuel or the unauthorized installation of a heli- coil insert in place of
the spark plug threads.
zInstall a new spark plug.
6. Inspect for overheating, identified by a white or light gray spots and with bluish- burnt
appearance of electrodes. This is caused by engine overheating, wrong type of fuel, loose spark
plugs, spark plugs with an incorrect heat range, low fuel pump pressure or incorrect ignition
timing.
zInstall a new spark plug. Klj . 2 ba
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meeting Ford specification WSS-
M97B44-D. Mixing coolants may degrade the coolant's
corrosion protection.
z Do not add alcohol, methanol, or brine, or any engine coolants mixed with alcohol or methanol
antifreeze. These can cause engine damage from overheating or freezing.
z Do not mix with recycled coolant unless it meets the requirements of Ford specification WSS-
M97B51- A1. Not all coolant recycling processes meet these Ford specifications. Use of such
coolants can harm the engine and cooling system components.
The coolant temperature sensor (4.6L) or cylinder head temperature sensor (3.8L) provides a signal to
the temperature gauge.
The optional block heater:
zelectrical heating element is installed in the core plug opening.
„uses a standard 110V electrical supply
z keeps the engine coolant warm during cold weather. Klj . 3 ba
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„
If coolant is low, add specified coolant mixture only.
„ If the engine coolant tests too weak, add straight engine coolant until the readings
are within acceptable levels.
„ If the engine coolant tests strong, remove some of the engine coolant and add
water until the readings are within acceptable levels.
5. If the concern remains after the inspection, determine the symptom(s) and GO to Symptom Chart
Symptom Chart
Pinpoint Tests
PINPOINT TEST A: LOSS OF COOLANT
Symptom Chart Condition
Possible Sources Action
z Loss of coolant zRadiator.
z Coolant pump seal.
z Radiator hoses.
z Heater hoses.
z Heater core.
z Engine gaskets.
z Degas bottle or
coolant expansion
tank. z
Go To Pinpoint Test
A .
z The engine overheats zThermostat.
z Coolant pump.
z Internal engine coolant
leak.
z Radiator.
z Cooling fan.
z Pressure relief cap or
radiator cap. z
Go To Pinpoint Test
B .
z The engine does not reach
normal operating temperature z
Thermostat. zGo To Pinpoint Test
C .
Test Step Result / Action to Take
A1 CHECK THE ENGINE COOLANT LEVEL
WARNING: Never remove the pressure relief cap
while the engine is operating or when the cooling system is
hot. Failure to follow these instructions can result in
damage to the cooling system or engine or personal injury.
To avoid having scalding hot coolant or steam blow out of
the degas bottle when removing the pressure relief cap,
wait until the engine is cooled, then wrap a thick cloth
around the pressure relief cap and turn it slowly. Step back Yes
GO to
A2 .
No
REFILL the engine
coolant as necessary.
GO to A2 . Klj . 3 ba
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PINPOINT TEST B: THE ENGINE OVERHEATS
Test Step Result / Action to
Take B1 CHECK THE ENGINE COOLANT LEVEL
WARNING: Never remove the pressure relief cap while
the engine is operating or when the cooling system is hot.
Failure to follow these instructions can result in damage to
the cooling system or engine or personal injury. To avoid
having scalding hot coolant or steam blow out of the degas
bottle when removing the pressure relief cap, wait until the
engine is cooled, then wrap a thick cloth around the
pressure relief cap and turn it slowly. Step back while the
pressure is released from the cooling system. When you are
sure all the pressure has been released, turn and remove
the pressure relief cap (still with a cloth). NOTE: If the engine
is hot, allow the engine to cool before proceeding.
z Key in OFF position.
z Check the engine coolant level at the degas bottle/coolant
expansion tank.
z Is the engine coolant OK? Yes
GO to
B2 .
No
REFILL the engine
coolant at the degas
bottle/coolant
expansion tank. Go To Pinpoint Test A .
B2 CHECK THE COOLANT CONDITION
z
Check the coolant for dirt, rust or contamination.
z Is the coolant condition OK? Yes
GO to
B3 .
No
FLUSH the engine
cooling system.
REFER to Engine and Radiator Flushing in
this section. TEST the
system for normal
operation. B3 CHECK FOR AN AIRFLOW OBSTRUCTION
z
Inspect the A/C condenser core and radiator for obstructions
such as leaves or dirt.
z Is there an obstruction? Yes
REMOVE the
obstruction. CLEAN the
A/C condenser core
and radiator. TEST the
system for normal
operation.
No
GO to
B4 .
B4 CHECK THE WATER THERMOSTAT OPERATION
z
Start the engine and allow the engine to run for ten minutes.
z Feel the inlet and outlet heater water hoses and the underside of
the upper radiator hose.
z Are the upper radiator hose and the heater water hoses
cold? Yes
INSTALL a new water
thermostat. REFER to
Thermostat
— 3.8L ,
Thermostat — 4.6L(2V)
or
Thermostat — 4.6L
(4V) in this section.
TEST the system for
normal operation.
No
GO to B5 . Klj . 5 ba
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To maintain the integrity of the coolant and the cooling system:
zAdd Motorcraft Premium Gold Engine Coolant VC -7-A (in Oregon VC -7-B) or equivalent
meeting Ford specification WSS- M97B51-A1 (yellow color). Use the same coolant that
was drained from the cooling system. Do not mix coolant types.
z Do not add/mix orange- colored Motorcraft Speciality Orange Engine Coolant VC- 2 or
equivalent meeting Ford specification WSS- M97B44-D. Mixing coolants may degrade the
coolant's corrosion protection.
z Do not add alcohol, methanol, or brine, or any engine coolants mixed with alcohol or
methanol antifreeze. These can cause engine damage from overheating or freezing.
z Do not mix with recycled coolant unless it meets the requirements of Ford specification
WSS- M97B51- A1. Not all coolant recycling processes meet these Ford specifications.
Use of such coolants can harm the engine and cooling system components.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
1. Place the heater temperature selector in the maximum cool position.
2. CAUTION: On 3.8L engines, the vent plug must be removed before radiator fill or
the engine may not fill completely.
NOTE: It is important to maintain engine coolant concentrate between 40 percent or - 24°C (-11°
F) and 60 percent or - 52°C (-62°F).
Fill the engine cooling system with 50/50 mixture of water and engine coolant.
3. After filling the engine cooling system, add coolant to the vent until full. Install the vent plug.
4. Leave the pressure relief cap off and run the engine until it reaches normal operating temperature.
5. Stop the engine and add the correct engine coolant mixture to the degas bottle/coolant expansion tank until the coolant level is between the COOLANT FILL LEVEL marks.
6. Turn the engine off and allow the cooling system to cool. Check the level in the degas bottle/coolant expansion tank, and add a 50/50 mix as needed. Filling — 4.6L (2V) Klj . 2 ba
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CAUTION: Vehicle cooling systems are filled with Motorcraft Premium Gold Engine
Coolant VC -7-A (in Oregon VC -7-B) or equivalent meeting Ford specification WSS- M97B51-A1
(yellow color). Always fill the cooling system with the same coolant that is present in the
system. Do not mix coolant types.
CAUTION: Engine coolant provides freeze protection, boil protection, cooling efficiency,
and corrosion protection to the engine and cooling components. In order to obtain these
protections, the engine coolant must be maintained at the correct concentration and fluid level
in the degas bottle.
When adding engine coolant, use a 50/50 mixture of engine coolant and deionized water.
To maintain the integrity of the coolant and the cooling system:
zAdd Motorcraft Premium Gold Engine Coolant VC -7-A (in Oregon VC -7-B) or equivalent
meeting Ford specification WSS- M97B51-A1 (yellow color). Use the same coolant that
was drained from the cooling system. Do not mix coolant types.
z Do not add/mix orange- colored Motorcraft Speciality Orange Engine Coolant VC- 2 or
equivalent meeting Ford specification WSS- M97B44-D. Mixing coolants may degrade the
coolant's corrosion protection.
z Do not add alcohol, methanol, or brine, or any engine coolants mixed with alcohol or
methanol antifreeze. These can cause engine damage from overheating or freezing.
z Do not mix with recycled coolant unless it meets the requirements of Ford specification
WSS- M97B51- A1. Not all coolant recycling processes meet these Ford specifications.
Use of such coolants can harm the engine and cooling system components.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
1. Remove the thermostat. For additional information, refer to Thermostat — 4.6L(2V) in this
section.
2. Disconnect the heater core coolant supply hose from the fitting at the rear of the manifold.
3. Add the coolant/water mixture through the thermostat opening until coolant appears at the heater core coolant supply outlet fitting at the rear of the manifold.
4. Install the heater hose, using an appropriately sized worm style clamp in place of the constant tension clamp.
5. Reinstall the thermostat gasket (O- ring) and the thermostat. For additional information, refer to
Thermostat — 4.6L(2V) in this section.
6. Add the correct engine coolant mixture to the degas bottle until the coolant level is between the Klj . 3 ba
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"COOLANT FILL LEVEL" marks and replace the pressure cap.
7. Select the maximum cool temperature setting.
8. Run the engine until it reaches operating temperature.
9. CAUTION: If the engine coolant temperature gauge does not move, the engine
coolant level in the engine is low and must be filled. Stop the engine, allow it to cool and
fill the cooling system.
Add the correct engine coolant mixture to the degas bottle until the coolant level is between the
"COOLANT FILL LEVEL" marks.
10. Repeat the two previous steps until the engine coolant mixture is between the "COOLANT FILL LEVEL" marks on the degas bottle. Turn off the engine and allow it to cool.
11. Check the freeze protection of the engine coolant mixture with the Battery/Anti- freeze Tester
014- R1060 or equivalent. Adjust freezing point range if necessary.
Filling — Cobra
CAUTION: Vehicle cooling systems are filled with Motorcraft Premium Gold Engine
Coolant VC -7-A (in Oregon VC -7-B) or equivalent meeting Ford specification WSS- M97B51-A1
(yellow color). Always fill the cooling system with the same coolant that is present in the
system. Do not mix coolant types.
CAUTION: Engine coolant provides freeze protection, boil protection, cooling efficiency,
and corrosion protection to the engine and cooling components. In order to obtain these
protections, the engine coolant must be maintained at the correct concentration and fluid level
in the degas bottle.
When adding engine coolant, use a 50/50 mixture of engine coolant and deionized water.
To maintain the integrity of the coolant and the cooling system:
zAdd Motorcraft Premium Gold Engine Coolant VC -7-A (in Oregon VC -7-B) or equivalent
meeting Ford specification WSS- M97B51-A1 (yellow color). Use the same coolant that
was drained from the cooling system. Do not mix coolant types.
z Do not add/mix orange- colored Motorcraft Speciality Orange Engine Coolant VC- 2 or
equivalent meeting Ford specification WSS- M97B44-D. Mixing coolants may degrade the
coolant's corrosion protection.
z Do not add alcohol, methanol, or brine, or any engine coolants mixed with alcohol or
methanol antifreeze. These can cause engine damage from overheating or freezing.
z Do not mix with recycled coolant unless it meets the requirements of Ford specification
WSS- M97B51- A1. Not all coolant recycling processes meet these Ford specifications.
Use of such coolants can harm the engine and cooling system components.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
1. Check all hose clamps for correct tightness. Make sure the radiator draincock is closed.
2. Place the heater temperature selector in maximum cool position. Klj . 4 ba
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3. Remove the pressure cap from the cooling system reservoir and the fill plug from the engine
crossover tube.
4. CAUTION: Do not fill the cooling system through the reservoir only. Coolant will not
enter the engine. Only the reservoir and the radiator will be filled and engine overheating
will occur.
Add coolant into the fill neck on the engine crossover tube until coolant reaches the top of the fill
neck on the cooling system reservoir.
5. Install the cooling system pressure cap on the reservoir.
6. Continue to fill the cooling system at the engine crossover fill neck until full.
7. Install the engine crossover tube fill plug.
8. WARNING: To avoid the possibility of personal injury or damage to the vehicle, do
not operate the engine with the hood open until the fan has been first examined for
possible cracks and separation.
CAUTION: If the engine temperature gauge does not move, coolant level is low in
the engine and must be filled. Stop the engine, allow to cool, and fill the cooling system
as outlined.
Run the engine until the thermostat opens (coolant flowing through the radiator lower hose
becomes hot).
9. Stop the engine and allow to cool.
10. Add coolant to the engine crossover tube fill neck until the cooling system is full.
11. Install the fill plug.
12. Repeat the fill procedure if necessary.
Filling — Mach I
CAUTION: Vehicle cooling systems are filled with Motorcraft Premium Gold Engine
Coolant VC -7-A (in Oregon VC -7-B) or equivalent meeting Ford specification WSS- M97B51-A1
(yellow color). Always fill the cooling system with the same coolant that is present in the
system. Do not mix coolant types.
CAUTION: Engine coolant provides freeze protection, boil protection, cooling efficiency,
and corrosion protection to the engine and cooling components. In order to obtain these
protections, the engine coolant must be maintained at the correct concentration and fluid level
in the degas bottle.
When adding engine coolant, use a 50/50 mixture of engine coolant and deionized water.
To maintain the integrity of the coolant and the cooling system:
zAdd Motorcraft Premium Gold Engine Coolant VC -7-A (in Oregon VC -7-B) or equivalent
meeting Ford specification WSS- M97B51-A1 (yellow color). Use the same coolant that Klj . 5 ba
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