2003 FORD MUSTANG low oil pressure

SPECIFICATIONS
SECTION 303-
01D: Engine — Mach I 4.6L (4V) 2003 Mustang Workshop Manual General Specifications
Item Specification
Metal Surface Cleaner
F4AZ-
19A536- RA WSE-
M5B392- A Silicone Gasket and Sealant F7AZ-19554-
EA WSE-
M4G323-
A4 Motorcraft Premium Gold Engine Coolant VC-7-
A (in Oregon VC-7-B) (Yellow
Color) WSS-
M97B51- A1 Pipe Sealant with Teflon® D8AZ-19554-
A WSK-
M2G350-
A2 Motorcraft MERCON® Super Premium 5W-
20 Motor Oil XO-5W20-QSP WSS-
M2C153- H Threadlock 262 E2FZ-19554-
B WSK-
M2G351-
A6
Engine Specifications Description Specification
GENERAL SPECIFICATIONS
Displacement 4.6L (4V) (281 CID)
Number of Cylinders 8
Bore and Stroke 90.2 x 90.0 mm (3.55 x 3.54 inch)
Firing Order 1-3-7-2-6-5-4-
8 Oil Pressure (HOT 1500 RPM) 138-
310 kPa Drive Belt Tension a
Combustion Chamber Volume (cc)
52.6±
0.5 cm c Valve Seats
·
Width— Intake 1.8-
2.2 mm (0.071- 0.086 inch) ·
Width— Exhaust 1.8-
2.2 mm (0.071- 0.086 inch) ·
Angle 45 degrees
·
Runout (T.I.R.) Max 0.05 mm (0.002 inch)
Valve Arrangement (Front-
to-Rear) c ·
(Left Hand) Intake: S-P-S-P-S-P-S-P
·
Exhaust: E-E-E-E-E-E-E-E
·
(Right Hand) Intake: P-S-P-S-P-S-P-S
·
Exhaust: (C) E-E-E-E-E-E-E-E
Valve Stem to Guide Clearance
·
Intake 0.020-
0.069 mm (0.00078- 0.00272 inch) ·
Exhaust 0.046-
0.095 mm (0.0018- 0.0037 inch) Klj . 1 ba
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z
are connected in series with the fuel pressure sensor.
z supply fuel from the fuel tank with a fuel pump mounted in the fuel tank.
A constant fuel pressure drop is maintained across the fuel injectors by the fuel pressure sensor. The
fuel pressure sensor:
zis positioned upstream from the fuel injectors on the fuel injection supply manifold.
Valve Train
The valve train operates as follows:
zball- tip hydraulic lash adjusters provide automatic lash adjustment.
z roller followers ride on the camshaft lobes, transferring the up-and- down motion of the
camshafts to the valves in the cylinder heads.
Positive Crankcase Ventilation System
All engines are equipped with a closed- type positive crankcase ventilation system recycling the
crankcase vapors to the upper intake manifold.
Lubrication System
The engine lubrication system operates as follows:
zoil is drawn into the oil pump through the oil pump screen cover and tube in the sump of the oil
pan.
z oil is pumped through the oil bypass filter on the left front side of the cylinder block.
z oil enters the main oil gallery where it is distributed to the crankshaft main journals and to both
cylinder heads.
z From the main journals, the oil is routed through cross- drilled passages in the crankshaft to
lubricate the connecting rod bearings. Controlled leakage through the crankshaft main bearings
and connecting rod bearings is slung radially outward to cool and lubricate the cylinder walls as
well as the entire connecting rod, piston and piston rings assembly.
z The left cylinder head is fed from a drilling into the supply passage feeding the main gallery at
the front of the cylinder block. The right cylinder head is fed from a drilling into the rear of the
main gallery. Main gallery pressure is reduced as it enters the cylinder head galleries through
fixed serviceable orifices located at the upper part of the feed passages. It is this reduced
pressure in the cylinder head galleries which feeds the camshaft journals, the hydraulic lash
adjusters and the primary and secondary timing chain tensioners.
z The camshaft lobe and roller followers are lubricated by splash created through valve train
operation.
Oil Pump
The lubrication system of the 4.6L (4V) engine is designed to provide optimum oil flow to critical
components of the engine through its entire operating range. The heart of the system is a positive
displacement internal gear oil pump using top seal rotors. Generically this design is known as a gerotor
pump, which operates as follows.
zThe oil pump is mounted on the front face of the cylinder block.
z The inner rotor is piloted on the crankshaft post and is driven through flats on the crankshaft. Klj . 2 ba
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z
System pressure is limited by an integral, internally- vented relief valve which directs the
bypassed oil back to the inlet side of the oil pump.
z Oil pump displacement has been selected to provide adequate volume to ensure correct oil
pressure both at hot idle and maximum speed.
z The relief valve calibration protects the system from excessive pressure during high viscosity
conditions.
z The relief valve is designed to provide adequate connecting rod bearing lubrication under high-
temperature and high- speed conditions.
Cooling System
The engine cooling system includes the following:
zradiator
z coolant pump
z the electric cooling fan motor and fan blade, activated by the variable control module
z the degas bottle, which aids in maintaining the correct volume of engine coolant
z thermostat
z upper radiator hose
z lower radiator hose
z heater coolant hoses
Drive Belt System
The 4.6L (4V) DOHC engine is equipped with a serpentine drive belt. To ensure maximum life, a
replacement drive belt should be of the same type as originally installed.
zThe accessories mounted on the front of the engine are belt- driven by the crankshaft.
z The serpentine drive belt is routed over each accessory pulley, driven by the crankshaft pulley
bolted to the crankshaft. For service procedures, including tensioning, refer to Section 303 - 05 . Klj . 3 ba
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IN-
VEHICLE REPAIR
Valve — Springs, Retainer and Valve Stem Seal
Removal 1. Remove the roller followers. For additional information, refer to Roller Followers in this section.
2. Remove the spark plugs. For additional information, refer to Section 303 - 07C .
3. Position the piston of the cylinder being serviced at the bottom of the stroke.
4. CAUTION: If air pressure has forced the piston to the bottom of the cylinder any
loss of air pressure will allow the valve to fall into the cylinder. If air pressure must be
removed support the valve prior to removal. Use compressed air in the cylinder to hold both valves in position. SECTION 303-
01D: Engine — Mach I 4.6L (4V) 2003 Mustang Workshop Manual Special Tool(s)
Compressor, Valve Spring
303-
452 (T93P-6565- AR) Installer, Valve Stem Oil Seal
303-
383 (T91P-6571- A) Compressor, Valve Spring
303-
567 (T97P-6565- AH) Spacer, Valve Spring
Compressor
303-
382 (T91P-6565- AH) Klj . 1 ba
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DESCRIPTION AND OPERATION
Engine Cooling
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.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
The 4.6L cooling system components include the:
zblock heater
z engine coolant temperature (ECT) sensor
z fan blade, fan motor and fan shroud assembly
z radiator
z pressure relief cap
z radiator draincock
z coolant pump
z coolant thermostat
z oil filter adapter
z radiator overflow hose
z upper radiator hose
z lower radiator hose
The radiator overflow hose circulates the coolant.
The coolant thermostat:
zcontrols the engine coolant temperature.
z allows for quicker engine warm- up.
The degas bottle/coolant expansion tank:
zprovides a location for service fill.
z contains coolant expansion and system pressurization.
z provides air separation during operation.
z replenishes the engine coolant to the system.
The engine coolant flows:
zfrom the lower radiator hose to the coolant pump.
z from the coolant pump to the engine block and the cylinder heads.
SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Engine Cooling
Inspection and Verification
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).
CAUTION: Check the coolant level, engine oil and transmission fluid, top off the coolant if
needed. If there is engine coolant in the engine oil or transmission fluid, the cause must be
corrected and oil/fluid changed or major component damage may occur.
1. Verify the customer's concern by operating the engine to duplicate the condition.
2. Inspect to determine if any of the following mechanical or electrical concerns apply.
SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual Special Tool(s)
Pressure Tester
014-
R1072 or equivalent 73III Automotive Meter
105-
R0057 or equivalent Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool Battery/Anti-Freeze Tester
014- R1060 or equivalent Klj . 1 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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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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