coolant temperature FORD MUSTANG 2003 Owner's Manual

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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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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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. 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.
1. Remove the air intake scoop. For additional information, refer to Section 303 - 12 .
2. Check all hose clamps for correct tightness. Make sure the radiator draincock is closed.
3. Place the heater temperature selector in maximum cool position.
4. Remove the pressure cap from the cooling system reservoir and the fill plug from the engine crossover tube.
5. 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.
6. Install the cooling system pressure cap on the reservoir.
7. Continue to fill the cooling system at the engine crossover fill neck until full.
8. Install the engine crossover tube fill plug.
9. 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).
10. Stop the engine and allow to cool.
11. Add coolant to the engine crossover tube fill neck until the cooling system is full.
12. Install the fill plug.
13. Repeat the fill procedure if necessary. Klj . 6 ba
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14. Install the air intake scoop. For additional information, refer to
Section 303 - 12 .
Bleeding 1. Select the maximum heater temperature and blower motor speed settings. Position the control to discharge air at A/C vents in instrument panel.
2. Start the engine and allow to idle. While engine is idling, feel for hot air at A/C vents.
3. CAUTION: If the air discharge remains cool and the engine coolant temperature
gauge does not move, the engine coolant level is low and must be filled. Stop the engine,
allow the engine to cool and fill cooling system.
Start the engine and allow it to idle until normal operating temperature is reached. Hot air should
discharge from A/C vents. The engine coolant temperature gauge should maintain a stabilized
reading in the middle of the NORMAL range. The upper radiator hose should feel hot to the
touch.
4. Shut the engine off and allow the engine to cool.
5. Check the engine for coolant leaks.
6. Check the engine coolant level in the degas bottle/coolant expansion tank and fill as necessary. Klj . 7 ba
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REMOVAL AND INSTALLATION
Bypass Tube —
Cobra
Removal and Installation 1. Drain the engine coolant. For additional information, refer to Cooling System Draining, Filling and Bleeding in this section.
2. Disconnect the radiator upper hose and the radiator lower hose.
3. Remove the supercharger belt. For additional information, refer to Section 303 - 05 .
4. Disconnect the engine coolant temperature sensor electrical connector and unclip the wiring harness from the stud.
5. NOTE: LH is shown, RH is similar.
Remove the coolant bypass nuts.
SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual Material
Item Specification
Motorcraft Premium Gold
Engine Coolant
VC
-7-A (in Oregon VC-7- B)
(yellow color) WSS-
M97B51-
A1 Klj . 1 ba
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REMOVAL AND INSTALLATION
Bypass Tube —
Mach I
Removal and Installation 1. Remove the air intake scoop and bracket. For additional information, refer to Section 303 - 12 .
2. Drain the engine coolant. For additional information, refer to Cooling System Draining, Filling and Bleeding in this section.
3. Disconnect the upper radiator hose from the bypass tube.
4. Disconnect the lower radiator hose. 5. Disconnect the engine temperature control (ECT) sensor electrical connector. SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual Material
Item Specification
Motorcraft Premium Gold
Engine Coolant
VC
-7-A (in Oregon VC-7- B)
(yellow color) WSS-
M97B51-
A1 Klj . 1 ba
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12 — Coolant reservoir bottle electrical connector
13 — Radio ignition interference capacitor electrical
connector
14 — Fuel injector electrical connectors
15 — Exhaust vacuum regulator (EVR) electrical
connector
16 — Differential pressure feedback EGR electrical
connector
17 — RH ignition coil electrical connectors
18 — Ignition coil electrical connectors
19 — Throttle position (TP) sensor electrical connector
20 — Idle air control (IAC) solenoid electrical connector
21 — Voltage regulator electrical connector
22 — Engine coolant temperature (ECT) electrical
connector
23 — Generator battery electrical connector
24 — Radio ignition interference capacitor electrical
connector
25 — Crankshaft position (CKP) sensor electrical
connector
26 — Air conditioning compressor clutch electrical
connector
27 — 16 pin electrical connector Klj . 3 ba
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