2003 FORD MUSTANG fuel

REMOVAL AND INSTALLATION
Fuel Injectors
Removal
WARNING: Do not smoke or carry lighted tobacco or open flame of any type when
working on or near any fuel related components. Highly flammable mixtures are always present
and can ignite. Failure to follow these instructions can result in personal injury.
WARNING: Fuel in the fuel system remains under high pressure even when the engine is
not running. Before working on or disconnecting any of the fuel lines or fuel system
components, the fuel system pressure must be relieved. Failure to follow these instructions
can result in personal injury.
1. Remove the supply manifold. For additional information, refer to Supply Manifold in this section.
2. Remove the eight fuel injectors from the supply manifold.
Installation CAUTION: The retaining clip must be in the upper groove on the injector or the injector
can become loose.
1. NOTE: Inspect the two O- rings from each fuel injector. Install new O- rings as needed.
NOTE: Lubricate the new O- rings with clean engine oil.
To install, reverse the removal procedure.
SECTION 303-
04D: Fuel Charging and Controls — Mach I 4.6L (4V) 2003 Mustang Workshop Manual Klj . 1 ba
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REMOVAL AND INSTALLATION
Wiring Harness
Removal
WARNING: Do not smoke or carry lighted tobacco or open flame of any type when
working on or near any fuel related components. Highly flammable mixtures are always present
and can ignite. Failure to follow these instructions can result in personal injury.
1. With the vehicle in neutral, position it on a hoist. For additional information, refer to Section 100 -
02 .
2. Disconnect the battery ground cable. For additional information, refer to Section 414 - 01 .
3. Remove the upper intake manifold. For additional information, refer to Section 303 - 01D .
4. Disconnect the following connectors: zThe 42 pin engine bulkhead electrical connector.
z The 16 pin electrical connector.
5. Separate the wiring harness from the dash panel.
6. Remove the RH ignition coil cover. zRemove the bolts.
z Remove the coil cover.
SECTION 303-
04D: Fuel Charging and Controls — Mach I 4.6L (4V) 2003 Mustang Workshop Manual Klj . 1 ba
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REMOVAL AND INSTALLATION
Supply Manifold
Removal
WARNING: Do not smoke or carry lighted tobacco or open flame of any type when
working on or near any fuel related components. Highly flammable mixtures are always present
and can ignite. Failure to follow these instructions can result in personal injury.
WARNING: Fuel in the fuel system remains under high pressure even when the engine is
not running. Before working on or disconnecting any of the fuel lines or fuel system
components, the fuel system pressure must be relieved. Failure to follow these instructions
can result in personal injury.
1. Disconnect the battery ground cable. For additional information, refer to Section 414 - 01 .
2. Remove the upper intake manifold. For additional information, refer to Section 303 - 01D .
3. Relieve the fuel pressure. For additional information, refer to Section 310 - 00 .
4. Disconnect the fuel line. For additional information, refer to Section 310 - 00 .
5. Position the wiring harness aside. zDisconnect the RH fuel injector electrical connectors.
z Separate the harness from the RH fuel supply manifold stud bolt.
6. Disconnect the fuel pressure sensor. zDisconnect the electrical connector.
z Disconnect the vacuum hose.
SECTION 303-
04D: Fuel Charging and Controls — Mach I 4.6L (4V) 2003 Mustang Workshop Manual Klj . 1 ba
32003 Mustang Workshop Manual
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7. Position the wiring harness aside.
zDisconnect the LH fuel injector electrical connectors.
z Separate the harness from the LH fuel supply manifold stud bolt.
8. Remove the fuel supply manifold. zRemove the four bolts.
Installation 1. NOTE: When the battery is disconnected and reconnected, some abnormal drive symptoms
may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven
16 km (10 mi) or more to relearn the strategy.
To install, reverse the removal procedure. Klj . 2 ba
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Component Tests
Starter Motor —Voltage Drop Test
WARNING: When servicing starter motor or carrying out other underhood work in the
vicinity of the starter motor, be aware that the heavy gauge battery input lead at the starter
solenoid is "electrically hot" at all times. A protective cap or boot is provided over this terminal
that must be installed after servicing. Be sure to disconnect the battery negative cable before
servicing the starter. Failure to follow these instructions may result in personal injury.
WARNING: When using a remote starter switch or jumper wire, be sure the ignition switch
is in the OFF position and the transmission is in PARK (A/T) or Neutral (M/T) with the parking
brake control fully applied.
Always make the Digital Multimeter connections at the component terminal rather than at the wiring
end connector. Making a connection at the wiring end connector could result in false readings because
the meter will not pick up a high resistance between the wiring connector and the component.
Starter Motor— Motor Feed Circuit
1. Make sure the battery is fully charged. Perform a battery load test. For additional information, refer to Section 414 - 00 .
2. Disconnect the inertia fuel shut off (IFS) switch.
3. Connect a remote starter switch between the starter solenoid S- terminal and the battery positive
(+) terminal.
4. Connect the Digital Multimeter positive lead to the battery positive (+) post. Connect negative lead to the starter solenoid M- terminal. brackets for cracks.
z Check the starter motor mounting
bolts for looseness.
z Is the starter motor mounted
correctly? GO to
D2 .
No
REINSTALL the starter motor correctly. REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this
section. D2 INSPECT THE STARTER MOTOR
z
Remove the starter motor; refer to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this section.
z Inspect the starter motor for
damage.
z Is the starter motor damaged? Yes
INSTALL a new starter motor. REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this section.
TEST the system for normal operation.
No
CHECK the starter drive. REFER to Component
Tests, Starter Drive Test in this section. INSTALL a
new starter motor. TEST the system for normal
operation. Klj . 8 ba
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DESCRIPTION AND OPERATION
Engine Ignition
The ignition coil (12029), which is mounted on the upper intake manifold, can be described as a coil
pack containing three separate coil units. Each coil unit is individually controlled by the powertrain
control module (PCM) (12A650) through separate wire leads. Each coil unit activates two spark plugs
wired in a series by the spark plug wires (12286).
zOne spark plug activates on the compression stroke and uses the majority of the ignition coil's
stored energy.
z The other spark plug activates on the exhaust stroke and uses very little of the ignition coil's
stored energy.
z Because the pairs of spark plugs are connected in a series, one spark will travel from ground to
the electrode while the other spark will travel from the electrode to ground.
The spark plug (12405):
zchanges the high voltage pulse into a spark which ignites the fuel and air mixture.
z originally equipped on the vehicle has a platinum- enhanced active electrode for long life.
The crankshaft position (CKP) sensor (6C315):
NOTE: Initial engine ignition timing is set at 10 degrees ± 2 degrees before top dead center (BTDC)
and is not adjustable.
zis a variable reluctance sensor triggered by a 36- minus-1 tooth trigger pulse wheel located on
the crankshaft (6303) inside the engine front cover (6019).
The sine wave type signal generated from the crankshaft position sensor provides two types of
information:
zposition of the crankshaft in 10 degree increments
z the crankshaft speed (rpm)
The powertrain control module (PCM) (12A650) uses this information to determine ignition coil turn ON
and turn OFF times and misfire detection.
For additional information, refer to Section 303 - 14 .
SECTION 303-
07A: Engine Ignition — 3.8L 2003 Mustang Workshop Manual Klj . 1 ba
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4. Inspect for gap bridged.
zThis can be identified by deposit build up closing the gap between electrodes.
z This may be caused by oil or carbon fouling.
z Clean the spark plug.
5. Inspect for oil fouling. zThis can be identified by wet black deposits on the insulator shell bore electrodes.
z This may be caused by excessive oil entering the combustion chamber through worn
rings and pistons, excessive clearance between valve guides and stems, or worn or
loose bearings. Correct the oil problem.
z Install a new spark plug.
6. Inspect for carbon fouling. zThis can be identified by black, dry, fluffy carbon deposits on the insulator tips, exposed
shell surfaces and electrodes.
z This may be caused by too cold a plug, dirty air cleaner, damaged fuel pump, too rich a
fuel mixture or excessive idling.
z Clean the spark plug. Klj . 2 ba
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7. Inspect for normal burning.
zThis can be identified by light tan or gray deposits on the firing tip.
8. Inspect for pre- ignition.
z This can be identified by melted electrodes and possibly a blistered insulator. Metallic
deposits on the insulator indicate engine damage.
z Install a new spark plug.
9. Inspect for overheating. zThis can be identified by a white or light gray insulator with small black or gray brown
spots and a bluish- burnt appearance of the electrodes.
z This may be caused by engine overheating, the wrong type of fuel, loose spark plugs, too
hot a plug, low fuel pump pressure or incorrect ignition timing.
z Install a new spark plug. Klj . 3 ba
52003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...