2003 FORD MUSTANG spark plugs

z
Change engine oil and install a new oil filter, lube front lower control arm and steering linkage
ball joints with zerk fittings (if equipped) every 4,800 km (3,000 miles) or 3 months.
z Inspect brake system and check battery electrolyte level (Patrol cars) every 8,000 km (5,000
miles).
z Install a new fuel filter every 24,000 km (15,000 miles).
z Change automatic transmission fluid, lubricate 4x2 wheel bearings, install new grease seals and
adjust bearings every 48,000 km (30,000 miles).
z Install new spark plugs and change transfer case fluid every 96,000 km (60,000 miles).
z Install a new cabin air filter as required.
When operating in dusty conditions such as unpaved or dusty roads:
zChange engine oil and install a new oil filter every 4,800 km (3,000 miles) or 3 months.
z Install a new fuel filter every 24,000 km (15,000 miles).
z Change automatic transmission fluid every 48,000 km (30,000 miles).
z Change transfer case fluid every 96,000 km (60,000 miles).
z Install a new engine air filter as required.
z Install a new cabin air filter as required.
When operating in off- road conditions:
z Change automatic transmission fluid every 48,000 km (30,000 miles).
z Change transfer case fluid every 96,000 km (60,000 miles).
z Install a new cabin air filter as required.
z Inspect and lubricate U- joints.
z Inspect and lubricate steering linkage ball joints with zerk fittings.
Checks and Services
Certain basic maintenance checks and inspections should be carried out at specified intervals. Any
recognized adverse condition should be corrected as soon as possible.
Maximum Oil Change Interval (Normal Schedule) z8,000 km (5,000 miles) or 6 months, whichever occurs first.
Maximum Oil Change Interval (Special Operating Conditions)
z4,800 km (3,000 miles) or 3 months.
Monthly Checks
Check each of the following items every month:
zAll interior and exterior lights.
z Tires for wear and correct air pressure. Klj . 2 ba
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z
Inspect wheel ends for end play and noise.
z Inspect engine cooling system and hoses.
z Inspect exhaust system and heat shields.
z Inspect steering linkage, suspension and (if equipped) driveshaft and ball joints.
z Rotate tires and inspect for wear.
z Install a new engine air filter.
z Install a new fuel filter.
z If equipped, install a new cabin air filter.
z Change automatic transmission/transaxle fluid on all vehicles equipped with AX4S, 4F50N,
4R100, 4F27E. Inspect automatic transmission fluid level using dipstick on all other vehicles, if
equipped.
z If equipped, install new climate controlled seat filters (Navigator, Lincoln LS and Aviator).
Additional services for natural gas and propane vehicles include inspecting fuel tanks, as well as
draining coalescent fuel filter bowl and installing a new filter.
152,000 Km (95,000 Miles)
zChange engine oil and install a new oil filter.
z Inspect tires for wear. Rotation recommended for optimal tire life.
160,000 Km (100,000 Miles)
zChange engine oil and install a new oil filter.
z Inspect accessory drive belt(s).
z Rotate tires and inspect for wear.
z Install new spark plugs.
z If filled with yellow coolant, change coolant or at 5 years, whichever comes first.
z Install a new PCV on all cars and light trucks under 6,000 pounds Gross Vehicle Weight (GVW).
z Drain coalescent fuel filter and replace filter (NGV).
168,000 Km (105,000 Miles)
zChange engine oil and install a new oil filter.
z Inspect automatic transmission fluid level if equipped with dipstick.
z Inspect brake pads, shoes, rotors, drums, brake lines, hoses and parking brake system.
z Inspect wheel ends for end play and noise.
z Inspect engine coolant system and hoses.
z Inspect steering linkage, suspension and (if equipped) driveshaft and ball joints.
z Rotate tires and inspect for wear.
z If equipped, install a new cabin air filter.
z If filled with green engine coolant, change coolant. 176,000 Km (110,000 Miles) Klj . 7 ba
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noise—
normally
accompanied by
vibration Powertrain/Drivetrain Mount Neutralizing in this
section.
z Damaged or
misaligned exhaust
system. z
INSPECT the exhaust
system for loose or broken
clamps and brackets.
CARRY OUT Exhaust System Neutralizing in this
section.
z Whistling noise—
normally
accompanied
with poor idle
condition z
Air intake system. zCHECK the air intake
ducts, air cleaner, throttle
body and vacuum hoses for
leaks and correct fit.
REPAIR or ADJUST as
necessary. REFER to
Section 303 - 12
z
Clunking noise zWater pump has
excessive end play or
imbalance. z
CHECK the water pump for
excessive end play.
INSPECT the water pump
with the drive belt off for
imbalance. INSTALL a new
water pump as necessary.
REFER to Section 303 -
03A .
z Generator has
excessive end play. z
CHECK the generator for
excessive end play.
REPAIR or INSTALL a new
generator. REFER to
Section 414 - 02 .
z Pinging noise zExhaust system leak. zINSPECT the exhaust
system for leaks. REPAIR
as necessary.
z Gasoline octane too
low. z
VERIFY with customer the
type of gasoline used.
CORRECT as necessary.
z Knock sensor
operation. z
CHECK the knock sensor.
INSTALL a new knock
sensor as necessary.
REFER to Section 303 - 14 .
z Incorrect spark
timing. z
CHECK the spark timing.
REPAIR as necessary.
z High operating
temperature. z
INSPECT cooling system
for leaks. CHECK the
coolant level. REFILL as
necessary. CHECK the
coolant for the correct mix
ratio. DRAIN and REFILL
as needed. CHECK engine
operating temperature is
within specifications.
REPAIR as necessary.
z Foul- out spark plug. zCHECK the spark plugs.
REPAIR or INSTALL new
spark plugs as necessary.
z Catalytic converter. zAcceptable noise.
z Knocking noise—
light knocking
noise, also z
Excessive clearance
between the piston
and the cylinder wall. z
Engine cold and at high
idle. Using an EngineEAR,
pull a spark plug or fuel Klj . 24 ba
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described as
piston slap. Noise
is most
noticeable when
engine is cold
with light to
medium
acceleration.
Noise disappears
as engine warms
injector connector until the
noise goes away. CARRY
OUT a cylinder bore
clearance to piston check.
INSTALL a new piston.
REFER to
Section 303 - 01A
for 3.8L engines or
Section 303 - 01B for 4.6L (2V)
engines.
z Knocking noise—
light double
knock or sharp
rap sound.
Occurs mostly
with warm engine
at idle or low
speeds in DRIVE.
Increases in
relation to engine
load. Associated
with poor
lubrication history z
Excessive clearance
between the piston
and the piston pin. z
INSTALL a new piston or
piston pin. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Knocking noise—
light knocking
noise is most
noticeable when
engine is warm.
Noise tends to
decrease when
vehicle is
coasting or in
neutral z
Excessive clearance
between the
connecting rod
bearings and the
crankshaft. z
Engine warm and at idle.
Using an EngineEAR,
PULL a spark plug or fuel
injector connector until the
noise goes away. INSTALL
new bearings. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Knocking— deep
knocking noise.
Noise is most
noticeable when
engine is warm,
at lower rpm and
under a light load
and then at float z
Worn or damaged
crankshaft main
bearings. z
CARRY OUT DERU test.
CHECK for noise with
vehicle at operating
temperature, during
medium to heavy
acceleration. CHECK at
idle with injector
disconnected, noise does
not change. INSTALL new
main bearings. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Knocking noise—
occurs mostly
with warm engine
at light/medium
acceleration z
Spark plugs. zCHECK the spark plug for
damage or wear. INSTALL
new spark plugs as
necessary.
z Carbon accumulation
in combustion
chamber. z
REMOVE carbon from
combustion chamber.
z Whine or
moaning noise z
Air intake system. zCHECK the air cleaner and
ducts for correct fit.
INSPECT the air intake
system for leaks or
damage. REPAIR as
necessary. Klj . 25 ba
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as necessary.
z Accelerator pedal
vibration— felt
through the pedal
as a buzz z
Throttle cable loose
or misrouted. z
INSPECT the throttle cable.
REPAIR as necessary.
REFER to Section 310 - 02 .
z Engine
vibration— mostly
at coast/neutral
coast. Condition
improves with
vehicle
accelerating z
Combustion
instability. z
CHECK the ignition system.
INSTALL new components
as necessary.
z Engine vibration
or shudder—
occurs with light
to medium
acceleration
above 56 km/h
(35 mph) z
Worn or damaged
spark plugs. z
INSPECT the spark plugs
for cracks, high resistance
or broken insulator.
INSTALL a new spark plug
(s) as necessary.
z Plugged fuel injector. zREPAIR or INSTALL a new
injector as necessary.
REFER to Section 303 - 04A
for 3.8L engines or
Section 303 - 04B for 4.6L (2V)
engines.
z Damaged spark plug
wire. z
INSPECT the spark plug
wires for damage. INSTALL
a new spark plug wire(s) as
necessary.
z Contaminated fuel. zINSPECT the fuel for
contamination. DRAIN the
fuel system and refill.
z Worn or damaged
torque converter. z
CHECK the torque
converter. INSTALL a new
torque converter as
necessary. REFER to
Section 307 - 01 .
Symptom Chart—
Idle Noise/Vibration Condition
Possible Sources Action
z Idle air control (IAC)
valve moan — occurs
on throttle tip- out z
IAC valve is
contaminated
with oil. z
GO to Component Tests in
this section.
z Accessory drive belt
chirp — occurs at idle
or high idle, cold or
hot. Most common
occurrence is during
humid weather z
Accessory drive
belt worn, or
pulley is
misaligned or
loose. z
INSPECT for loose or
misaligned pulleys. CHECK
the drive belt for wear or
damage. INSTALL new
pulley(s)/drive belt, or
accessory drive components
as necessary. REFER to
Section 303 - 05 .
z Accessory drive
bearing hoot —
occurs at idle or high
idle in cold
temperatures of
approximately +4°C z
Accessory drive
idler or
tensioner pulley
bearing is
experiencing
stick/slip z
Go To Pinpoint Test C . Klj . 28 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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1. If compression improves considerably, piston rings are faulty.
2. If compression does not improve, valves are sticking or seating incorrectly.
3. If two adjacent cylinders indicate low compression pressures and squirting oil on each piston
does not increase compression, the head gasket may be leaking between cylinders. Engine oil
or coolant in cylinders could result from this condition.
Use the Compression Pressure Limit Chart when checking cylinder compression so that the
lowest reading is within 75 percent of the highest reading.
Cylinder Leakage Detection
When a cylinder produces a low reading, use of the Engine Cylinder Leak Detection/Air Pressurization
Kit will be helpful in pinpointing the exact cause.
The leakage detector is inserted in the spark plug hole, the piston is brought up to dead center on the
compression stroke, and compressed air is admitted.
Once the combustion chamber is pressurized, a special gauge included in the kit will read the
percentage of leakage. Leakage exceeding 20 percent is excessive.
While the air pressure is retained in the cylinder, listen for the hiss of escaping air. A leak at the intake
valve (6507) will be heard in the throttle body (9E926). A leak at the exhaust valve (6505) can be
heard at the tail pipe. Leakage past the piston rings will be audible at the positive crankcase ventilation
(PCV) connection. If air is passing through a blown head gasket to an adjacent cylinder, the noise will
be evident at the spark plug hole of the cylinder into which the air is leaking. Cracks in the cylinder
block or gasket leakage into the cooling system may be detected by a stream of bubbles in the radiator
(8005).
Oil Consumption Test
The following diagnostic procedure is used to determine the source of excessive internal oil
consumption. 1. NOTE: Oil use is normally greater during the first 16,100 km (10,000 miles) of service. As
mileage increases, oil use generally decreases. Vehicles in normal service should get at least
1,450 km per liter (900 miles per quart) after 16,000 km (10,000 miles) of service. High speed
driving, towing, high ambient temperature and other factors may result in greater oil use.
Define excessive oil consumption, such as the number of miles driven per liter (quart) of oil
used. Also determine customer's driving habits, such as sustained high speed operation,
towing, extended idle and other considerations.
2. Verify that the engine has no external oil leak as described under Engine Oil Leaks in the Diagnosis and Testing portion of this section.
3. Verify that the engine has the correct oil level dipstick (6750).
4. Verify that the engine is not being run in an overfilled condition. Check the oil level at least five minutes after a hot shutdown with the vehicle parked on a level surface. In no case should the
level be above MAX or the letter F in FULL. If significantly overfilled, carry out Steps 6a through
6d.
5. Verify the spark plugs are not oil saturated. If the spark plugs are oil saturated and compression is good it can be assumed the valve seals or valve guides are at fault. Klj . 9 ba
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6. Carry out an oil consumption test:
a. Drain the engine oil, remove the oil bypass filter (6714) and refill with one liter (quart) less than
the recommended amount.
b. Run the engine for three minutes (10 minutes if cold), and allow the oil to drain back for at least five minutes with the vehicle on a level surface.
c. Remove oil level dipstick and wipe clean. (Do not wipe with anything contaminated with silicone compounds.) Reinstall the oil level dipstick, being sure to seat it firmly in the oil level indicator
tube (6754). Remove the oil level dipstick and draw a mark on the back (unmarked) surface at
the indicated oil level. This level should be about the same as the MIN or ADD mark on the face
of the oil level dipstick.
d. Add one liter (quart) of oil. Restart the engine and allow to idle for at least two minutes. Shut off the engine and allow the oil to drain back for at least five minutes. Mark the oil level dipstick,
using the procedure above.
e. Record the vehicle mileage. f. Instruct the customer to drive the vehicle as usual and perform the following:
„Check the oil level regularly at intervals of 160 to 240 km (100- 150 miles).
„ Return to the service point when the oil level drops below the lower (MIN or ADD) mark
on the oil level dipstick.
„ Add only full liters (quarts) of the same oil in an emergency. Note the mileage at which
the oil is added.
g. Check the oil level under the same conditions and at the same location as in Steps 6c and 6d.
„Measure the distance from the oil level to the UPPER mark on the oil level dipstick and
record.
„ Measure the distance between the two scribe marks and record.
„ Divide the first measurement by the second.
„ Divide the distance driven during the oil test by the result. This quantity is the
approximate oil consumption rate in kilometers per liter or in miles per quart.
h. If the oil consumption rate is unacceptable, go to Step 7.
7. Check the positive crankcase ventilation (PCV) system. Make sure the system is not plugged.
8. Check for plugged oil drain- back holes in the cylinder heads and cylinder block.
9. If the condition still exists after performing the above steps, go to Step 10.
10. Perform a cylinder compression test or perform a cylinder leak detection test with Engine Cylinder Leak Detection/Air Pressurization Kit. This can help determine the source of oil
consumption such as valves, piston rings or other areas.
11. NOTE: After determining if new parts should be installed, make sure correct parts are used.
Check valve guides for excessive guide clearance. Install new all valve stem seals (6571) after
verifying valve guide clearance.
12. Worn or damaged internal engine components can cause excessive oil consumption. Small deposits of oil on the tips of spark plugs can be a clue to internal oil consumption. If internal oil
consumption still persists, proceed as follows:
a. Remove the engine from the vehicle and place it on an engine work stand. Remove the intake manifolds (9424), cylinder heads, oil pan (6675) and oil pump (6600).
b. Check piston ring clearance, ring gap and ring orientation. Repair as necessary.
c. Check for excessive bearing clearance. Repair as necessary.
13. Repeat the oil consumption test (Step 6) to confirm the oil consumption concern has been resolved. Klj . 10 ba
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