2003 FORD MUSTANG ignition

REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Damaged charging
system/battery. z
REFER to Section 414 - 00 .
z Burnt valve. zINSTALL a new valve.
z Worn piston. zINSTALL a new piston.
z Worn piston rings. zINSTALL new piston rings.
z Worn cylinder. zREPAIR or INSTALL a new
cylinder block.
z Damaged head
gasket. z
INSTALL a new head gasket.
z Damaged cooling
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Poor idling zVacuum leaks. zRefer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Malfunctioning or
damaged ignition
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Malfunctioning or
damaged fuel
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Damaged valve
tappet or lash
adjuster. z
INSTALL a new valve tappet or
lash adjuster.
z Damaged valve
tappet guide or lash
adjuster. z
INSTALL a new valve tappet
guide or valve tappet.
z Incorrect valve-to-
valve seat contact. z
REPAIR or INSTALL a new
valve or valve seat.
z Damaged head
gasket. z
INSTALL a new head gasket.
z Abnormal
combustion z
Malfunctioning or
damaged fuel
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Malfunctioning or
damaged ignition
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Malfunctioning or
damaged air intake
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis Klj . 3 ba
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z
Seized or heat
damaged
crankshaft main
bearing. z
INSTALL a new crankshaft main
bearing.
z Excessive
crankshaft end
play. z
INSTALL a new thrust bearing or
crankshaft (6303).
z Excessive
connecting rod
bearing clearance. z
INSTALL a new connecting rod
bearing or connecting rod
(6200).
z Heat damaged
connecting rod
bearing (6211). z
INSTALL a new connecting rod
bearing.
z Damaged
connecting rod
bushing (6207). z
INSTALL a new connecting rod
bushing.
z Worn cylinder. zREPAIR or INSTALL a new
cylinder block (6010).
z Worn piston (6108)
or piston pin
(6135). z
INSTALL a new piston or piston
pin.
z Damaged piston
rings. z
INSTALL new piston rings.
z Bent connecting
rod. z
INSTALL a new connecting rod.
z Malfunctioning
valve tappet (6500)
or lash adjuster. z
INSTALL a new valve tappet or
lash adjuster.
z Excessive valve
tappet or lash
adjuster clearance. z
ADJUST clearance or INSTALL
a new valve tappet guide or
valve tappet.
z Broken valve spring
(6513). z
INSTALL a new valve spring.
z Excessive valve
guide clearance. z
ADJUST clearance or INSTALL
a new valve guide (6510) or
valve.
z Insufficient
power z
Malfunctioning or
damaged ignition
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Malfunctioning or
damaged fuel
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Malfunctioning or
damaged air intake
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Damaged or
plugged exhaust
system. z
INSPECT exhaust system.
z Incorrect tire size. zREFER to Section 204 - 04 .
z Dragging brakes. zREFER to Section 206 - 00 . Klj . 5 ba
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z
intake manifold gaskets
z cylinder head gaskets
z oil bypass filter
z oil filter adapter
z engine front cover
z oil filter adapter and filter body
z oil level indicator tube connection
z oil pressure sensor
Leakage Points— Under Engine—With Vehicle on Hoist
z oil pan gaskets (6710)
z oil pan sealer
z oil pan rear seal (6723)
z engine front cover gasket
z crankshaft front seal (6700)
z crankshaft rear oil seal (6701)
z crankshaft main bearing cap side bolts
z oil filter adapter and filter body
z oil cooler, if equipped
Leakage Points— With Transmission and Flywheel Removed
z crankshaft rear oil seal
z rear main bearing cap parting line
z rear main bearing cap and seals
z flywheel mounting bolt holes (with flywheel [6375] installed)
z camshaft rear bearing covers (6266) or pipe plugs at the end of oil passages
Oil leaks at crimped seams in sheet metal parts and cracks in cast or stamped parts can be detected
when using the dye method.
Compression Test— Compression Gauge Check
1. Make sure the oil in the crankcase is of the correct viscosity and at the correct level and that the battery (10655) is correctly charged. Operate the vehicle until the engine is at normal operating
temperature. Turn the ignition switch to the OFF position, then remove all the spark plugs
(12405).
2. Set the throttle plates in the wide- open position.
3. Install a compression gauge such as the Compression Tester in the No. 1 cylinder.
4. Install an auxiliary starter switch in the starting circuit. With the ignition switch in the OFF position, and using the auxiliary starter switch, crank the engine a minimum of five compression
strokes and record the highest reading. Note the approximate number of compression strokes Klj . 7 ba
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4. WORN RINGS OR DILUTED OIL: When the engine is accelerated (dotted needle), the needle
drops to 0 kPa (0 in- Hg). Upon deceleration, the needle runs slightly above 74 kPa (22 in- Hg).
5. STICKING VALVES: When the needle (dotted) remains steady at a normal vacuum but occasionally flicks (sharp, fast movement) down and back about 13 kPa (4 in- Hg), one or more
valves may be sticking.
6. BURNED OR WARPED VALVES: A regular, evenly- spaced, downscale flicking of the needle
indicates one or more burned or warped valves. Insufficient hydraulic lash adjuster or hydraulic
lash adjuster (HLA) clearance will also cause this reaction.
7. POOR VALVE SEATING: A small but regular downscale flicking can mean one or more valves are not seating.
8. WORN VALVE GUIDES: When the needle oscillates over about a 13 kPa (4 in- Hg) range at idle
speed, the valve guides could be worn. As engine speed increases, the needle will become
steady if guides are responsible.
9. WEAK VALVE SPRINGS: When the needle oscillation becomes more violent as engine rpm is increased, weak valve springs are indicated. The reading at idle could be relatively steady.
10. LATE VALVE TIMING: A steady but low reading could be caused by late valve timing.
11. IGNITION TIMING RETARDING: Retarded ignition timing will produce a steady but somewhat low reading.
12. INSUFFICIENT SPARK PLUG GAP: When spark plugs are gapped too close, a regular, small pulsation of the needle can occur.
13. INTAKE LEAK: A low, steady reading can be caused by an intake manifold or throttle body gasket leak.
14. BLOWN HEAD GASKET: A regular drop of fair magnitude can be caused by a blown head gasket or warped cylinder head- to-cylinder block surface.
15. RESTRICTED EXHAUST SYSTEM: When the engine is first started and is idled, the reading may be normal, but as the engine rpm is increased, the back pressure caused by a clogged
muffler (5230), kinked tail pipe or other concerns will cause the needle to slowly drop to 0 kPa
(0 in-Hg). The needle then may slowly rise. Excessive exhaust clogging will cause the needle to
drop to a low point even if the engine is only idling.
16. When vacuum leaks are indicated, search out and correct the cause. Excess air leaking into the system will upset the fuel mixture and cause concerns such as rough idle, missing on
acceleration or burned valves. If the leak exists in an accessory unit such as the power brake
booster (2005), the unit will not function correctly. Always fix vacuum leaks.
Excessive Engine Oil Consumption
The amount of oil an engine uses will vary with the way the vehicle is driven in addition to normal
engine- to-engine variation. This is especially true during the first 16,100 km (10,000 miles) when a new
engine is being broken in or until certain internal engine components become conditioned. Vehicles
used in heavy- duty operation may use more oil. The following are examples of heavy- duty operation:
z trailer towing applications
z severe loading applications
z sustained high speed operation Klj . 12 ba
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9. Install the valve covers.
Valve Train Analysis— Engine Running, Camshaft Lobe Lift— Push Rod Engine
Check the lift of each lobe in consecutive order and make a note of the readings. 1. Remove the valve covers.
2. Remove the rocker arm seat bolts, rocker arm seat (6A528) and rocker arms.
Typical Engine With Push Rods
3. Make sure the valve tappet is seated against camshaft (6250). Install (1) Dial Indicator Gauge with Holding Fixture so the ball socket adapter of the indicator is on top of the valve tappet or (2)
Dial Indicator Gauge Adapter is on top of push rod and in same plane as valve tappet push rod
movement.
4. Remove the spark plugs.
5. Connect an auxiliary starter switch in the starting circuit. Crank the engine with ignition switch in OFF position. Bump crankshaft over until valve tappet is on base circle of camshaft lobe. At this
point, valve tappet will be in its lowest position. If checking during engine assembly, turn
crankshaft using a socket or ratchet.
6. Zero the dial indicator. Continue to rotate crankshaft slowly until valve tappet is in fully- raised
position (highest indicator reading).
7. NOTE: If lift on any lobe is below specified service limits, install a new camshaft, and new valve
tappets.
Remove the Dial Indicator with Holding Fixture, Dial Indicator Gauge Adapter, and auxiliary
starter switch.
8. Install rocker arm seats, rocker arms and rocker arm seat bolts.
9. Install valve covers.
10. Install spark plugs.
Valve Train Analysis— Engine Running, Valve Tappet
Valve tappet noise can be caused by any of the following:
zexcessive valve tappet gap (collapsed) Klj . 16 ba
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4. Inspect for normal burning.
zCheck for light tan or gray deposits on the firing tip.
5. Inspect for pre- ignition, identified by melted electrodes and a possibly damaged insulator.
Metallic deposits on the insulator indicate engine damage. This may be caused by incorrect
ignition timing, wrong type of fuel or the unauthorized installation of a heli- coil insert in place of
the spark plug threads.
zInstall a new spark plug.
6. Inspect for overheating, identified by a white or light gray spots and with bluish- burnt
appearance of electrodes. This is caused by engine overheating, wrong type of fuel, loose spark
plugs, spark plugs with an incorrect heat range, low fuel pump pressure or incorrect ignition
timing.
zInstall a new spark plug. Klj . 2 ba
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a
20- 200 seconds to leakdown 3.18 mm (0.125 in) with 225 Newtons (50 pounds) load and tappet filled
with leak- down fluid. —
desired Connecting rod bearing-
to-crankshaft clearance
— allowable 0.022-
0.069 mm (0.00086- 0.0027 in) Connecting rod side clearance 0.11-
0.49 mm (0.0047- 0.0193 in) Balance Shaft
Journal diameter 52.108-
52.082 mm (2.0515- 2.0505 in) Bore inside diameter 55.689-
55.664 mm (2.192- 2.191 in) Maximum runout 0.025 mm (0.001 in)
End play 0.075-
0.200 mm (0.003- 0.008 in)
Torque Specifications Description Nm lb-
ft lb-
in EGR transducer bracket-
to-intake manifold bolts 10 — 89
Ignition coil-
to-intake manifold bolts 6 — 53
Water outlet tube-
to-intake manifold stud bolt 10 — 89
EGR tube-
to-EGR valve nut 40 30 —
Water outlet tube-
to-front water pump bolt 10 — 89
Fuel supply manifold bolts 10 — 89
LH valve cover-
to-cylinder head bolts 10 — 89
LH valve cover-
to-cylinder head stud bolts 10 — 89
EGR tube-
to-exhaust manifold nut 40 30 —
RH valve cover-
to-cylinder head bolts 10 — 89
RH valve cover-
to-cylinder head stud bolts 10 — 89
Coolant recovery reservoir-
to-cylinder head stud bolts 10 — 89
Coolant recovery reservoir-
to-bracket bolts 5 — 44
Crankshaft pulley bolt 160 118 —
Camshaft position sensor bolts 3 — 27
Camshaft synchronizer-
to-front cover bolt 25 18 —
Front cover-
to-cylinder block bolts 25 18 —
Radiator fan shroud-
to-radiator bolts 9 — 80
Camshaft thrust plate-
to-cylinder block bolts 12 9 —
Camshaft synchronizer drive gear-
to-camshaft bolt 45 33 —
Timing chain tensioner-
to-cylinder block bolts 12 9 —
Exhaust manifold-
to-cylinder head nuts 33 24 —
Power steering pump bracket-
to-water pump nuts 20 15 —
Power steering pump bracket-
to-generator bracket bolts 20 15 —
Generator bracket-
to-cylinder head bolts 40 30 —
Exhaust manifold studs 8 — 71
A/C compressor bracket-
to-cylinder head bolts 48 35 —
A/C compressor bracket-
to-cylinder head nut 48 35 — Klj . 4 ba
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DESCRIPTION AND OPERATION
Engine
The 3.8L engine has:
za V- block with six cylinders and splayed crankpins.
z a distributorless ignition system.
z a multiport, sequential fuel injection (SFI) system.
z overhead valves.
z hydraulic valve tappets for automatic lash adjustment.
z connecting rod parting faces that are unique with an interference fit.
z an engine dynamic balance shaft.
SECTION 303-
01A: Engine — 3.8L 2003 Mustang Workshop Manual Klj . 1 ba
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