2003 FORD MUSTANG check engine

„
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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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:
Allow the engine to cool before checking the engine
coolant level.
z Key in OFF position.
z Visually check the engine coolant level at the degas bottle or
coolant expansion tank.
z Is the engine coolant level within specification? A2 CHECK THE PRESSURE RELIEF CAP
z
Carry out the Cap— 3.8L or Cap—4.6L test. Go to Component
Tests in this section.
z Is pressure relief cap/radiator cap OK? Yes
GO to
A3 .
No
INSTALL a new
pressure relief
cap/radiator cap. TEST
the system for normal
operation. A3 CHECK THE ENGINE COOLANT FOR INTERNAL LEAK
z
Key in OFF position.
z Inspect the engine coolant in degas bottle/coolant expansion
tank for signs of transmission fluid or engine oil.
z Is oil or transmission fluid evident in the coolant? Yes
If engine oil is evident,
REFER to
Section 303 -
00 . If transmission fluid
is evident, REPAIR or
INSTALL a new radiator
as necessary.
No
GO to A4 .
A4 CHECK THE ENGINE AND THE TRANSMISSION FOR
COOLANT z
Remove the oil level dipstick from the engine and the
transmission.
z Is coolant evident in the oil or transmission fluid? Yes
If coolant is in engine,
REFER to
Section 303 -
00 . If coolant is in
transmission, REPAIR
or INSTALL a new
radiator as necessary.
To repair the automatic
transmission, REFER to
Section 307 - 01 .
No
GO to A5 .
A5 PRESSURE TEST THE ENGINE COOLING SYSTEM
z
Pressure test the engine cooling system. Go to Component
Tests in this section.
z Does the engine cooling system leak? Yes
REPAIR or install new
components. TEST the
system for normal
operation.
No
The cooling system is
operational. GO to
Symptom Chart
. Klj . 4 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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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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1. Turn the engine OFF.
2.
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).
Check the engine coolant level; refer to Cooling System Draining, Filling and Bleeding in this
section.
3. Connect Radiator Heater Core Pressure Tester to the degas bottle nipple and vent hose. Install a pressure test pump to the quick- connect fitting of the test adapter.
4. CAUTION: Do not pressurize the cooling system beyond 152 kPa (22 psi).
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.
5. If the pressure relief cap does not hold pressure, remove and wash the pressure relief cap in clean water to dislodge all foreign particles from the gaskets. Check the sealing surface in the
filler neck.
6. If 110 kPa (16 psi) cannot be reached, install a new pressure relief cap. If more than 124 kPa (18 psi) shows on gauge, install a new pressure relief cap.
7. CAUTION: If the pressure drops, check for leaks at the engine- to-heater core hoses,
engine- to-radiator hoses, water valve hose (if applicable), oil cooler return tube gasket
(6N789), radiator and heater core or other system components and connections. Any
leaks which are found must be corrected and the system rechecked.
Pressurize the engine cooling system as described in Step 4 (using a pressure relief cap that
operates within the specified upper and lower pressure limits). Observe the gauge reading for
approximately two minutes; refer to General Specifications. Pressure should not drop during this
time.
8. Release the system pressure by loosening the pressure relief cap. Check the engine coolant level and replenish, if necessary, with the correct engine coolant mixture; refer to Cooling System Draining, Filling and Bleeding in this section.
Cap — 3.8L
1. Inspect the radiator cap and seals for damage or deterioration. Install a new radiator cap if necessary.
2. Fit the radiator cap to Radiator/Heater Core Pressure Tester Kit, using the aftermarket adapter.
3. NOTE: If the plunger of the pressure tester is depressed too fast, an incorrect pressure reading
will result. Slowly pump the pressure tester until the pressure gauge stops increasing and note the highest Klj . 7 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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