2003 FORD MUSTANG fuel

DESCRIPTION AND OPERATION
Engine
WARNING: Do not operate the engine with the hood open until the fan blade has been first
examined for possible cracks and separation.
The 4.6L (4V) (281 CID) Cobra engine is a V- 8 with the following features:
z intercooled supercharger
z dual overhead camshafts
z four valves per cylinder
z sequential multiport fuel injection (SFI)
z an aluminum intake manifold
z aluminum cylinder heads
z a cast aluminum, 90-degree V- cylinder block
z individually chain- driven camshafts with a hydraulic timing chain tensioner on each timing chain
z the electronic ignition system with eight ignition coils
Identification
Always refer to these labels when replacement parts are necessary or when checking engine
calibrations. The engine parts often differ within a CID family. Verification of the identification codes will
ensure that the correct parts are obtained. These codes contain all the pertinent information relating to
the dates, optional equipment and revisions. The Ford Master Parts Catalog contains a complete
listing of the codes and their application.
Code Information
The engine code information label, located on the side of the valve cover and the front side of the
valve cover, contains the following:
zengine build date
z engine plant code
z engine code
Exhaust Emission Control System
Operation and necessary maintenance of the exhaust emission control devices used on this engine is
covered in the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
Induction System
The sequential multiport fuel injection (SFI) provides the fuel/air mixture needed for combustion in the
cylinders. The eight solenoid- operated fuel injectors:
z are mounted in the lower intake manifold.
z meter fuel into the air intake stream in accordance with engine demand.
SECTION 303-
01C: Engine — Cobra 4.6L (4V) 2003 Mustang Workshop Manual Klj . 1 ba
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z
are positioned so that their tips direct fuel just ahead of the engine intake valves.
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. Klj . 2 ba
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Item Part Number Description
1 12B637 Wiring harness
2 9C986 Fuel pulse damper
3 9F792 Fuel injection supply manifold
4 9F593 Fuel injector
5 — Stud
6 9D475 Exhaust gas recirculation valve
7 W701232 Bolt
8 N806979 Stud Klj . 5 ba
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IN-
VEHICLE REPAIR
Lower Intake Manifold
Removal and Installation 1. Drain the engine coolant. For additional information, refer to Section 303 - 03A in this section.
2. Drain the supercharger coolant. For additional information, refer to Section 303 - 03B .
3. Release the fuel system pressure. For additional information, refer to Section 310 - 00 .
4. Disconnect the radiator upper hose, radiator lower hose and the supercharger degas hose.
5. Remove the supercharger belt. For additional information, refer to Section 303 - 05 .
6. Disconnect the coolant hose.
SECTION 303-
01C: Engine — Cobra 4.6L (4V) 2003 Mustang Workshop Manual Material
Item Specification
Motorcraft Premium Engine
Coolant
VC
-4-A (in Oregon VC- 5, in
Canada CXC- 10) (green color) ESE-
M97B44-
A 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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7. Remove the air cleaner outlet tube. For additional information, refer to
Section 303 - 12 .
8. Disconnect the throttle position (TP) sensor and the idle air control (IAC) valve electrical connectors.
9. Disconnect the vacuum hose.
10. Disconnect the fuel hose spring lock coupling. For additional information, refer to Section 310 -
00 .
11. Disconnect the accelerator controls. zDisconnect the accelerator cable.
z If equipped, disconnect the speed control cable. 12. Remove the accelerator cable bracket bolts. Klj . 2 ba
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13. Release the clip and position the accelerator cable bracket and the cables aside.
14. Disconnect the electrical connectors from the fuel pulse damper, exhaust gas recirculation
(EGR) vacuum regulator solenoid, supercharger bypass vacuum solenoid, and the differential
pressure feedback EGR system.
15. Disconnect the vacuum hoses from the differential pressure feedback EGR system.
16. Disconnect the vacuum hoses from the supercharger bypass vacuum solenoid and the actuator. Klj . 3 ba
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17. Disconnect the vacuum hoses from the fuel pulse damper and the EGR vacuum regulator
solenoid.
18. Disconnect the vacuum hose from the EGR valve.
19. Disconnect the vacuum hoses at the back of the supercharger and position the vacuum harness aside.
20. Remove the vacuum accessory bracket mounting nut. Klj . 4 ba
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25. Separate the fuel charging wiring harness from the fuel injection supply manifold in four places
and position the harness aside.
26. Remove the ten bolts and the intake manifold, and the supercharger and fuel supply manifold as an assembly.
27. NOTE: Inspect the intake manifold gaskets and install new gaskets, if necessary.
NOTE: Install new bypass tube O- rings and lubricate them, using premium engine coolant.
To install, reverse the removal procedure. zTighten the intake manifold bolts in the sequence shown. Klj . 6 ba
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