2003 FORD MUSTANG gas type

DESCRIPTION AND OPERATION
Engine Emission Control
CAUTION: Do not remove any part of the engine emission control system. Operating the
engine without the engine emission control system will reduce fuel economy and engine
ventilation. This will weaken engine performance and shorten engine life.
The engine emission control consists of the:
zpositive crankcase ventilation (PCV) system.
z exhaust gas recirculation (EGR) system.
Typical Vehicle Emission Control Information (VECI) Decal
The Vehicle Emission Control Information (VECI) decal shows:
zthe components of the emission control system.
z the correct vacuum hose routing.
SECTION 303-
08: Engine Emission Control 2003 Mustang Workshop Manual Item Part Number Description
1 — Adjustment procedure notes
2 — Ignition timing specification
3 — Engine vacuum hose routing (typical)
4 — Spark plug gap specification
5 — Engine type Klj . 1 ba
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8 7A106 Body assembly —
front pump (part of 7A103) 9 7A136 Gasket —
front pump 10 7H169 Gear —
pump inner gerotor (part of 7A103) 11 7H169 Gear —
pump outer gerotor (part of 7A103) 12 7A108 Support assembly —
front pump 13 N605787-
S Bolt —
M8-1.25 x 25 hex flange head (5- attaches
7A108 to 7A103) 14 7D014 Washer —
front pump support thrust — select fit
No. 1 15 7D020 Seals —
reverse clutch cylinder (2 req'd) 16 7D019 Seals —
forward clutch cylinder (2 req'd) 17 7F225 Seal —
intermediate clutch piston inner 18 7F224 Seal —
intermediate clutch piston outer 19 7E005 Piston kit —
intermediate clutch 20 7A609 Intermediate clutch anti-
rattle clip (model
dependent) 21 7B442 Plate —
intermediate clutch external spline (select
fit) (steel) 22 7B164 Plate assembly —
intermediate clutch internal
spline (friction) 23 7B066 Plate —
intermediate clutch pressure 24 7F196 Band assembly —
overdrive 25 391267-
S Ring —3-
21/64 retains type SU external (retains
7F262 to 7F215) 26 7F271 Clutch assembly —intermediate one-
way clutch 27 7D044 Drum assembly — reverse clutch
28 7D403 Seal —
reverse clutch piston outer 29 7D402 Piston assembly —
reverse clutch 30 7D404 Seal reverse clutch piston inner
31 7D256 Ring —
reverse clutch piston pressure 32 7B070 Spring —
reverse clutch piston return 33 7A577 Spring —
reverse clutch piston spring 34 7B066 Plate —
reverse clutch front pressure 35 7B164 Plate —
reverse clutch internal spline (friction) 36 7B442 Plate —
reverse clutch external spline (steel) 37 7B066 Plate —
reverse clutch rear pressure 38 7B497 Seals —
input shaft (2 req'd) 39 7D483 Retainer —
reverse clutch pressure plate —
( select fit) 40 7A166 Bearing and race assembly —
forward clutch No.
2 41 7F207 Cylinder and input shaft assembly —
forward
clutch 42 7A548 Seal —
forward clutch piston outer Klj . 3 ba
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144 7G326 Nested spring
— 1-2 (inner spring) (vehicle
dependent) 145 7F247 Cover and seal assembly — 1-
2 accumulator 146 7384 Ring — 2-
1/16 retaining type HU internal (retains
7H300 to 7005) 147 N807178-
S1000 Bolt —
M6-1.0 x 18 hex head (12- attaches
reinforcing plate to valve body) 148 7F282 Plate —
valve body reinforcing (part of 7A100) 149 7C155 Gasket —
valve body separator upper 150 7A008 Plate —
control valve body separator (part of
7A100) 151 7D100 Gasket —
valve body separator lower 152 7D174 Valve —
converter drainback 153 7A091 Body assembly —
main control 154 7H173 Gasket —
valve body cover plate 155 7C034 Plate —
valve body cover (part of 7A100) 156 N807178-
S1000 Bolt —
M6-1.0 x 18 hex head (11- attaches 7C034
to 7A100 (part of 7A100) 157 7A100 Control assembly —
main (model dependent) 158 7A098 Filter and seal assembly —
fluid 159 7A191 Gasket —
transmission pan 160 7A194 Pan — transmission
161 N605785-
S1036 Bolt —
M8-1.25 x 18 hex flange head (14-
attaches 7A194 to 7005) 162 7L027 Magnet —
ceramic case (part of 7A194) 163 N808947-
S1300 Bolt —
M8-1.25 x 46 hex shoulder pilot (2-
attaches 7C034 to 7A100) 164 N807179-
S1000 Bolt —
M6-1.0 x 52 hex flange head (12- attaches
7A100 to 7005) 165 7H111 Retainer — solenoid
166 7E195 Ball —
1/4 diameter coast booster valve shuttle (8
req'd) 167 7H187 Screen —
solenoid pressure supply 168 N800670-
S1000 Bolt —
M6-1.0 x 40 hex flange head (13- attaches
7A100 to 7005) 169 7E332 Spring assembly —
manual valve detent 170 7Z276 Seal —
0.864 x 0.070 O- ring (2 req'd) 171 7G276 Bulkhead assembly — wiring connector
172 7G276 Bulkhead assembly —
connector (molded lead
frame) 173 7Z484 Seal —
6.07 x 1.70 O- ring (2 req'd) 174 7G484 Solenoid valve —
transmission shift 175 7G136 Solenoid valve —
transmission torque converter
clutch 176 N807178-
S1000 Bolt —
M6-1.0 x 16 hex head (retains 7D136 and
7G484 to 7A100) Klj . 7 ba
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following areas of possible leakage should also be checked to determine if engine oil leakage is
causing the concern.
a. Leakage at the engine valve cover gasket may allow oil to flow over the torque converter housing or seep down between the torque converter housing and cylinder block causing oil to
be present in or at the bottom of the torque converter housing.
b. Oil galley plug leaks will allow oil to flow down the rear face of the cylinder block to the bottom of the torque converter housing.
c. Leakage at the crankshaft rear oil seal will work back to the flexplate, and then into the torque converter housing.
d. Leakage at engine oil pressure sensor.
Leak Check Test 1. Remove the fluid level indicator and note the color of the fluid. Original factory fill fluid is dyed red to aid in determining if leakage is from the engine or transmission. Unless a considerable
amount of makeup fluid has been added or the fluid has been changed, the red color should
assist in pinpointing the leak.
2. Remove the torque converter housing cover. Clean off any fluid from the top and bottom of the torque converter housing, front of the case and rear face of the engine and oil pan. Clean the
torque converter area by washing with a suitable nonflammable solvent and blow dry with
compressed air.
3. Wash out the torque converter housing, the front of the flexplate and the converter drain plugs. The torque converter housing may be washed out using cleaning solvent and a squirt- type oil
can. Blow all washed areas dry with compressed air.
4. Start and run the engine until the transmission reaches its normal operating temperature. Observe the back of the cylinder block and top of the torque converter housing for evidence of
fluid leakage. Raise the vehicle on a hoist; refer to Section 100 - 02 and run the engine at fast
idle, then at engine idle, occasionally shifting to the Overdrive and Reverse ranges to increase
pressure within the transmission. Observe the front of the flexplate, back of the cylinder block
(in as far as possible), and inside the torque converter housing and front of the case. Run the
engine until fluid leakage is evident and the probable source of leakage can be determined.
Leak Check Test With Black Light Used With 12 Volt Master UV Diagnostic Inspection Kit
Oil soluble aniline or fluorescent dyes premixed at the rate of 2.5ml (1/2 teaspoon) of dye powder to
0.235L (1/2 pint) of transmission fluid have proved helpful in locating the source of fluid leakage. Such
dyes may be used to determine whether an engine oil or transmission fluid leak is present, or if the
fluid in the fluid cooler leaks into the engine cooling system. A black light must be used with the
fluorescent dye solution. Klj . 4 ba
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DESCRIPTION AND OPERATION
Climate Control System
WARNING: To avoid accidental deployment and possible injury, the air bag system
backup power supply must be depleted before repairing any climate control components. To
deplete the backup power supply, disconnect the battery ground cable and wait one minute.
Failure to follow these instructions may result in personal injury.
WARNING: Carbon monoxide is colorless, odorless and dangerous. If it is necessary to
operate the engine with the vehicle in a closed area such as a garage, always use an exhaust
collector to vent the exhaust gases outside the closed area.
WARNING: R- 134a is classified as a safe refrigerant, but misuse can make it dangerous.
The following precautions must be observed:
zAlways wear safety goggles when repairing an air conditioning system.
z Avoid contact with liquid refrigerant R- 134a. R-134a vaporizes at approximately - 25°C (-
13°F) under atmospheric pressure and it will freeze skin tissue.
z Never allow refrigerant R- 134a gas to escape in quantity in an occupied space. R- 134a is
non- toxic, but it will displace the oxygen needed to support life.
z Never use a torch in an atmosphere containing R- 134a gas. R-134a is non-toxic at all
normal conditions, but when it is exposed to high temperatures, such as a torch flame, it
decomposes. During decomposition it releases irritation and toxic gases (as described in
the MSDS sheet from the manufacturer). Decomposition products are hydrofluoric acid,
carbon dioxide and water.
z Do not allow any portion of the charged air conditioning system to become too hot. The
pressure in an air conditioning system rises as the temperature rises and temperatures
of approximately 85°C (185°F) can be dangerous.
z Allow the engine to cool sufficiently prior to carrying out maintenance or serious burns
and injury can occur.
CAUTION: To avoid damaging the vehicle or A/C components, the following precautions
must be observed:
zThe A/C refrigerant of all vehicles must be identified and analyzed prior to refrigerant
charging. Failure to due so can contaminate the shop bulk refrigerant and other vehicles.
z Do not add R- 12 refrigerant to an A/C system that requires the use of R- 134a refrigerant.
These two types of refrigerant must never be mixed. Doing so can damage the A/C
system.
z Charge the A/C system with the engine running only at the low- pressure side to prevent
refrigerant slugging from damaging the A/C compressor.
z Use only R- 134a refrigerant. Due to environmental concerns, when the air conditioning
system is drained, the refrigerant must be collected using refrigerant recovery/recycling
equipment. Federal law REQUIRES that R- 134a be recovered into appropriate recovery
equipment and the process be conducted by qualified technicians who have been
certified by an approved organization, such as MACS, ASI etc. Use of a recovery machine
dedicated to R- 134a is necessary to reduce the possibility of oil and refrigerant
incompatibility concerns. Refer to the instructions provided by the equipment manufacturer when removing refrigerant from or charging the air conditioning system. SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Klj . 1 ba
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evaporator core, it absorbs heat from the passenger compartment airflow passing over the plate/fin
sections of the A/C evaporator core. This addition of heat causes the refrigerant to boil (convert to a
gas). The now cooler passenger compartment air can no longer support the same humidity level of the
warmer air and this excess moisture condenses on the exterior of the evaporator coils and fins and
drains outside the vehicle.
The suction accumulator/drier (19C836) is designed to remove moisture from the refrigerant and to
prevent any liquid refrigerant that may not have been vaporized in the A/C evaporator core from
reaching the A/C compressor. The A/C compressor is designed to pump refrigerant vapor only, as
liquid refrigerant will not compress and can damage the A/C compressor.
The refrigerant cycle is now repeated with the A/C compressor again increasing the pressure and
temperature of the refrigerant.
The A/C cycling switch (19E561) interrupts compressor operation before the external temperature of
the A/C evaporator core gets low enough to cause the condensed water vapor (excess humidity) to
turn to ice. It does this by monitoring low side line pressure. It is known that a refrigerant pressure of
approximately 210 kPa (30 psi) will yield an operating temperature of 0°C (32°F). The A/C cycling
switch controls system operation in an effort to maintain this temperature.
The high side line pressure is also monitored so that the A/C compressor operation can be interrupted
if system pressure becomes too high.
The A/C compressor pressure relief valve (19D644) will open and vent refrigerant to relieve unusually
high system pressure.
Clutch Cycling Orifice Tube Type Refrigerant System Klj . 4 ba
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Heater Core
WARNING: Carbon monoxide gas is colorless, odorless and dangerous. If it is necessary
to operate the engine with the vehicle in a closed area such as a garage, always use an exhaust
collector to vent the exhaust gases outside the closed area. Failure to follow these instructions
may result in personal injury.
1. NOTE: Testing of returned heater cores reveals that a large percentage of heater cores are
good and did not require installation of a new heater core. If a heater core leak is suspected, the
heater core must be tested by following the Plugged Heater Core Component Test before the
Heater Core Pressure Test. Carry out a system inspection by checking the heater system
thoroughly as follows:
Inspect for evidence of coolant leakage at the heater water hose to heater core attachments. A
coolant leak in the heater water hose could follow the heater core tube to the heater core and
appear as a leak in the heater core.
CAUTION: Spring- type clamps are installed as original equipment. Installation and
overtightening of non- specification clamps can cause leakage at the heater water hose
connection and damage the heater core.
2. Check the integrity of the heater water hose clamps.
Heater Core— Plugged
WARNING: The heater core inlet hose will become too hot to handle if the system is
working correctly.
1. Check to see that the engine coolant is at the correct level.
2. Start the engine and turn on the heater.
3. When the engine coolant reaches operating temperature, feel the heater core outlet hose to see if it is hot.
If it is not hot:
zthe heater core may have an air pocket.
z the heater core may be plugged.
z the thermostat is not working correctly.
Heater Core— Pressure Test
Use the radiator/heater core pressure tester to carry out the pressure test. 1. NOTE: Due to space limitations, a bench test may be necessary for pressure testing.
Drain the coolant from the cooling system. For additional information, refer to Section 303 - 03A
or
Section 303 - 03B .
2. Disconnect the heater water hoses from the heater core. For additional information, refer to Klj . 37 ba
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An A/C compressor pressure relief valve is incorporated into the compressor A/C manifold and tube to:
zrelieve unusually high refrigerant system discharge pressure buildups. For specifications
regarding operating pressure(s), refer to Section 412 - 00 .
z prevent damage to the A/C compressor and other system components.
z avoid total refrigerant loss by closing after the excessive pressure has been relieved.
A/C Condenser Core
The A/C condenser core has the following characteristics:
zIt is an aluminum fin and tube design heat exchanger located in front of the vehicle radiator
(8005).
z It cools compressed refrigerant gas by allowing air to pass over fins and tubes to extract heat
and by condensing gas to liquid refrigerant as it is cooled.
Refrigerant Lines
The condenser to evaporator tube (19835) contains the high pressure liquid refrigerant upstream of the
evaporator core orifice.
The A/C manifold and tube (19D734) is attached to the A/C compressor, is sealed with O- ring seals,
and has the following features:
zThe upstream side contains low pressure refrigerant gas.
z The downstream side contains high pressure refrigerant gas and a fitting used to mount a
serviceable high pressure A/C charge port valve.
z The downstream side also contains a fitting used to mount the refrigerant containment switch
(3.8L) or dual- function pressure switch (4.6L). A long- travel Schrader-type valve stem core is
installed in the fitting so that the switch can be removed without discharging the A/C system. Klj . 4 ba
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