2003 FORD MUSTANG coolant temperature

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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3. If the inspection reveals an obvious concern that can be readily identified, repair as necessary.
4.
CAUTION: Some 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.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC-6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
Inspect the coolant condition. 1. Inspect the coolant color.
„If Motorcraft Premium Gold Engine Coolant (yellow color) VC-7- A (in Oregon VC-
7- B) or equivalent meeting Ford specification WSS-M97B51- A1 has a clear or
pale yellow color, this indicates higher water content than required.
„ Dark brown can indicate unauthorized stop leak may have been used. Use
Motorcraft Cooling System Stop Leak Pellets VC- 6 or equivalent meeting Ford
specification ESE-M99B37- 5 except as noted in ES-F6SE-19A511- AA only.
„ A light or reddish brown color indicates that rust may be present in the cooling
system. Flush the system and refill with the correct mixture of water and engine
coolant.
„ An iridescent sheen on top of the coolant can indicate a trace of oil is entering the
system. For additional information on engine diagnosis, refer to Section 303 - 00 .
„ A milky brown color may indicate that either engine oil or transmission fluid is
entering the cooling system. If transmission fluid is suspected, the cause may be a
leaky radiator. Pressure test the cooling system. For additional information, refer
to component tests in this section. If engine oil is suspected the cause of the leak
may be internal to the engine. For additional information, refer to Section 303 - 00 .
2. If the engine coolant appearance is acceptable, test the engine coolant freezing point
range with the battery and anti- freeze tester. The freezing point should be in the range -
40°C to - 20°C (-50°F to - 10°F). If the vehicle is driven in cold climates less than - 32°C (-
34°F), it may be necessary to increase the coolant concentration to get adequate freeze
protection.
„Maximum coolant concentration is 60% coolant/40% water.
„ Minimum coolant concentration is 40% coolant/60% water. 3. Adjust coolant range and level, if necessary: Visual Inspection Chart
Mechanical
z
Leaks
z Hoses
z Hose clamps
z Water gasket
z Head gaskets
z Intake manifold gasket
z Coolant pump
z Radiator
z Degas bottle/coolant expansion tank
z Heater core
z Fan/fan clutch
z Engine coolant temperature sensor (4.6L)
z Cylinder head temperature sensor (3.8L)
z Circuitry Klj . 2 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 C: THE ENGINE DOES NOT REACH NORMAL
OPERATING TEMPERATURE
Component Tests
Pressure Test —
3.8L
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).
1. Remove the radiator cap. Fill the radiator as needed. Fit the pressure tester to the radiator neck, using an aftermarket adapter.
2. CAUTION: Do not pressurize the cooling system beyond 110 kPa (16 psi).
Pump the cooling system to a maximum of 102 kPa (14.9 psi) and hold for 2 minutes. If the
pressure drops within this time, inspect for leaks and repair as necessary. Pressure Test — 4.6L B5 CHECK THE COOLING FAN OPERATION
z
Carry out the cooling fan component tests. Go to Component
Tests.
z Is the cooling fan operation OK? Yes
For diagnosis and
testing of the engine,
REFER to
Section 303 -
00 .
No
INSTALL a new fan
component as
necessary. TEST the
system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE ENGINE
TEMPERATURE z
Start the engine and allow the
engine to idle for ten minutes.
z Feel the inlet and 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
For diagnosis and testing of the engine coolant
temperature gauge, REFER to Section 413 - 01 . Klj . 6 ba
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pressure reading. Release pressure and repeat the test. Install a new radiator cap if the
pressure is not 99.3-
121.4 kPa (14.4-17.6 psi).
Cap — 4.6L
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).
1. Remove the pressure relief cap from the degas bottle.
2. Follow the instructions from the pressure tester.
3. NOTE: If the plunger of the pump is depressed too quickly, an erroneous pressure reading will
result.
Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops
increasing and note the highest pressure reading obtained.
4. If the pressure test gauge readings are not within specifications, install a new pressure relief cap. If the pressure test gauge readings are within specifications, carry out the cooling system
Pressure Test.
Thermostat — Water
A new water thermostat should be installed only after the following electrical and mechanical tests
have been carried out.
Thermostat — Electrical Test
CAUTION: Always vent the exhaust to the outside when carrying out this test.
NOTE: The electrical thermostat test is most accurate if carried out at less than 37.8°C (100°F)
ambient air. This test may be carried out with or without the hood open and with the engine warm or
cold.
1. Check the engine coolant level. Fill as needed.
2. With the ignition OFF, remove the engine coolant temperature (ECT) (4.6L) or cylinder head temperature (CHT) (3.8L) sensor harness connector and attach ECT (4.6L) or CHT (3.8L)
Sensor "T" Cable as a jumper between the powertrain control module (PCM) (12A650) and the
ECT (4.6L) or CHT (3.8L) sensor. Attach the 73III Automotive Meter to the ECT (4.6L) or CHT
(3.8L) Sensor "T" Cable. Voltage values (0- 5 V) may now be monitored while the sensor retains
its connection to the wiring harness.
An appropriate diagnostic tool may be used to monitor the ECT on vehicles equipped with data link connector (DLC). Klj . 8 ba
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3.
NOTE: Running this test with the vehicle in gear or with the A/C compressor clutch engaged
(running) will cause incorrect diagnosis.
Place the transmission in PARK (P) or NEUTRAL (N).
4. Start the engine and allow the engine to idle throughout this test. Allow the engine to run for 2 minutes, then record the ECT (4.6L) or CHT (3.8L) voltage. Record the ECT (4.6L) or CHT
(3.8L) voltage every 60 seconds. When the ECT (4.6L) or CHT (3.8L) voltage trend changes
direction or only changes slightly (0.03 volts or less) from the previous reading, record this as
the thermostat opening voltage. Use the voltage and corresponding coolant temperature chart
listed below for 4.6L engines only.
5. If the thermostat opening voltage is greater than 0.75 volts and less than 82°C (180°F), install a new water thermostat.
6. If the thermostat opening voltage is less than 0.75 volts and greater than 82°C (180°F), the water thermostat is good and a new water thermostat should not be installed. GO to Symptom Chart for further instructions.
Thermostat — Mechanical Test
1. Remove the water thermostat.
2. Check the water thermostat for seating. Hold the water thermostat up to a lighted background. Leakage of light around the thermostat valve at room temperature indicates that a new water
thermostat should be installed. Some water thermostats have a small leakage notch at one
location on the perimeter of the thermostat valve, which is considered normal.
3. Immerse the water thermostat in a boiling coolant and water mixture.
4. See the General Specifications chart for water thermostat opening temperatures.
Radiator Leak Test, Removed From the Vehicle CAUTION: Never leak test an aluminum radiator in the same water that copper/brass
radiators are tested in. Flux and caustic cleaners may be present in the cleaning tank and they
will damage aluminum radiators.
NOTE: Always install plugs in the oil cooler fittings before leak- testing or cleaning any radiator.
NOTE: Clean the radiator before leak- testing to avoid contamination of tank. Coolant Temperature °C (°F) ECT (Volts)
22 (71) 3.00
43 (109) 2.01
71 (159) 1.01
82 (180) 0.75
91 (195) 0.059
97 (206) 0.050
105 (221) 0.040 Klj . 9 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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"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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