low oil pressure FORD MUSTANG 2003 Repair Manual

Condition.
Shift Linkage
·
Damaged or incorrectly
adjusted ·
Inspect and repair as required. Verify transmission shift cable
adjustment; refer to Section 307 - 05 . Adjust transmission shift cable
as necessary. After repairing transmission shift cable, verify the digital
transmission range (TR) sensor is correctly adjusted. Adjust the
digital TR sensor as necessary. Incorrect Pressures
·
Low forward clutch
pressure, low line
pressure ·
Check pressure at line and forward clutch tap. Refer to Line Pressure
Chart for specification. If pressures are low, check the following
components: oil filter and seal assembly, main controls, pump
assembly, forward clutch assembly. Fluid Filter and Seal
Assembly
·
Plugged, damaged ·
Install a new filter and seal assembly. ·
Filter seal damaged Main Controls
·
3- 4 shift valve, main
regulator valve, manual
valve — stuck,
damaged ·
Inspect for damage. Repair as required. ·
Bolts not tightened to
specifications ·
Tighten bolts to specifications. ·
Gaskets damaged ·
Inspect gaskets for damage and install a new gasket. ·
2- 3 accumulator and
seals damaged ·
Inspect piston, seals and bore for damage. Repair as required. ·
Pressure regulator
valve ·
Inspect the diameter for wear. Pump Assembly
·
Bolts not tightened to
specifications ·
Tighten bolts to specifications. ·
Porosity/cross
leaks/ball missing or
leaking, plugged hole ·
Inspect for porosity and leaks. Repair as required. ·
No. 3 and No. 4 seal
rings damaged ·
Inspect seals for damage. Repair as required. ·
Gaskets damaged ·
Inspect for damage and install a new gasket. Forward Clutch
Assembly
·
Seals, piston damaged ·
Inspect seals for damage. Repair as required. ·
Check balls damaged,
missing, mislocated,
not seating correctly ·
Inspect for mislocation, poor seating, damage. Install a new cylinder
as required. ·
Friction elements
damaged or worn ·
Check for abnormal wear, damage. Repair as required. One-
Way Clutch
Assembly (Planetary) ·
Worn, damaged or
assembled incorrectly ·
Inspect for damage. Repair as required. Output Shaft Klj . 4 ba
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·
Damaged ·
Inspect for damage. Install new components as required.
Engagement Concern: No Reverse Possible Component Reference/Action
202 —
ELECTRICAL ROUTINE ·
No Electrical Concerns 302 —
HYDRAULIC/MECHANICAL ROUTINE Fluid
·
Incorrect level ·
Adjust fluid to correct level. ·
Condition ·
Inspect condition of fluid. Shift Linkage
·
Damaged or incorrectly
adjusted ·
Inspect and repair as required. Verify transmission shift cable
adjustment; refer to Section 307 - 05 . Adjust transmission shift
cable as necessary. After repairing transmission shift cable, verify
that the digital TR sensor is correctly adjusted. Adjust the digital
TR sensor as necessary. Incorrect Pressures
·
Low reverse clutch
pressure, low reverse band
pressure, low line pressure ·
Check pressure at line pressure tap; refer to Line Pressure Chart
for specifications. If pressures are low, check the following
components: oil filter and seal assembly, main controls, reverse
servo, pump assembly, reverse clutch assembly. Fluid Filter and Seal
Assembly
·
Plugged, damaged ·
Install a new filter and seal assembly. Main Controls
·
No. 6 shuttle ball, manual
valve, main regulator valve,
1- 2 accumulator seals
stuck or damaged ·
Inspect for damage. Repair as required. ·
Loose bolts ·
Tighten bolts to specifications. ·
Gasket damaged ·
Inspect for damage and install a new gasket. Low/Reverse Servo
·
Seals (piston and cover)
damaged ·
Inspect for damage. Repair as required. ·
Servo cover retaining ring
damaged ·
Anchor pins (case)
damaged Pump Assembly
·
Loose bolts ·
Tighten bolts to specifications. ·
Porosity/cross leaks/ball
missing or leaking, plugged
hole ·
Inspect pump assembly. Install new as required. ·
Gasket damaged ·
Inspect for damage and install a new gasket. ·
No. 1 and 2 seal rings
damaged ·
Inspect for damage. Repair as required. Reverse Clutch Assembly Klj . 5 ba
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·
Seals, piston damaged ·
Inspect for damage. Repair as required. ·
Check ball missing or
damaged ·
Friction elements damaged
or worn Low/Reverse Band
·
Band, servo, anchor pins
damaged or worn ·
Inspect for damage. Repair as required.
Engagement Concern: Harsh Reverse Possible Component Reference/Action
203 —
ELECTRICAL ROUTINE Powertrain Control System
·
Electrical inputs/outputs,
vehicle wiring harnesses,
PCM, TFT sensor, EPC
solenoid ·
Carry out Self-Test; refer to the Powertrain Control/Emissions
Diagnosis (PC/ED) manual for diagnosis and testing of the
Powertrain Control System. Carry out engagement test, EPC test
and Go To Pinpoint Test B or
Go To Pinpoint Test D . Check idle
speed. Repair as required. Clear DTCs, road test and repeat Self-
Test. 303 —
HYDRAULIC/MECHANICAL ROUTINE Fluid
·
Incorrect level ·
Adjust fluid to correct level. ·
Condition ·
Inspect condition of fluid. Engine Driveline
·
Looseness in the
driveshaft, U- joints or the
engine mounts ·
Repair as required. Shift Linkage
·
Damaged or incorrectly
adjusted ·
Inspect and repair as required. Verify transmission shift cable
adjustment; refer to Section 307 - 05 . Adjust transmission shift
cable as necessary. After repairing transmission shift cable, verify
that the digital TR sensor is correctly adjusted. Adjust the digital
TR sensor as necessary. Incorrect Pressures
·
High line pressure, high
EPC pressure ·
Check pressure at line and EPC pressure taps; refer to Line
Pressure Chart for specifications. If high, check the following
components: main controls, oil filter and seal assembly. Fluid Filter and Seal
Assembly
·
Plugged or damaged ·
Install a new filter and seal assembly. ·
Filter seal damaged Main Controls
·
No. 6 shuttle ball, No. 5
check ball, manual valve,
main regulator valve stuck,
damaged or missing ·
Inspect for damage. Repair as required. ·
Bolts not tightened to
specifications ·
Tighten bolts to specifications. Klj . 6 ba
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Possible Component Reference/Action
206 —
ELECTRICAL
ROUTINE ·
No Electrical Concerns 306 —
HYDRAULIC/MECHANICAL ROUTINE Fluid
·
Incorrect level ·
Adjust fluid to correct level. ·
Condition ·
Inspect condition of fluid. Shift Linkage
·
Damaged or incorrectly
adjusted ·
Inspect and repair as required. Verify transmission shift cable
adjustment; refer to Section 307 - 05 . Adjust transmission shift cable
as necessary. After repairing transmission shift cable, verify that the
digital TR sensor is correctly adjusted. Adjust the digital TR sensor as
necessary. Incorrect Pressures
·
Low forward clutch
pressure, low line
pressure, low EPC
pressure ·
Check pressure at line, forward clutch and EPC taps; refer to Line
Pressure Chart for specifications. If pressures are low, check the
following components: oil filter and seal assembly, main controls and
pump assembly. Fluid Filter and Seal
Assembly
·
Plugged, damaged ·
Install a new filter and seal assembly. ·
Filter seal damaged Main Controls
·
3- 4 shift valve, main
regulator valve stuck or
damaged ·
Inspect and repair as required. ·
Bolts not tightened to
specifications ·
Tighten bolts to specifications. ·
Gaskets damaged ·
Inspect for damage and repair as required. Case
·
2- 3 or 1- 2 accumulator,
bore damaged or stuck ·
Inspect for damage. Repair as required. Pump Assembly
·
Bolts not tightened to
specification ·
Tighten bolts to specifications. ·
Porosity/cross leaks ·
Inspect pump assembly. Repair as required. ·
Gaskets damaged ·
Inspect for damage. Repair as required. ·
No. 3 and No. 4 seal
rings damaged ·
Inspect for damage. Repair as required. Forward Clutch
Assembly
·
Seals, piston damaged ·
Inspect for damage. Repair as required. ·
Check balls missing,
damaged ·
Inspect for mislocation, poor seating, damage. Install a new cylinder
as required. ·
Friction elements
damaged, worn ·
Check for damage. Repair as required. Klj . 10 ba
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X = pressure applied Adjust the digital TR sensor as necessary.
Incorrect Pressures
·
Low reverse clutch pressure,
low reverse band pressure, low
line pressure
z Forward Off, Intermediate
Off, Direct X
z Forward Off, Intermediate
X, Direct Off
z Forward Off, Intermediate
X, Direct X
z Forward X, Intermediate
Off, Direct X
z Forward X, Intermediate X,
Direct Off
z Forward X, Intermediate X,
Direct X
z Forward X, Intermediate
Off, Direct Off ·
Check for which pressures are on and refer to Band/Clutch
Application Chart 601 and corresponding routines.
„ 324, 301
„ 325, 301
„ 323, 324, 325, 301
„ 324
„ 325
„ 323, 324, 325
„ Refer to appropriate mechanical diagnosis. Mechanical
·
Bands, clutches or seals
damaged or worn ·
Refer to Transmission Disassembly and Assembly.
Shift Concerns: No Manual 1st Gear Possible Component Reference/Action
216 —
ELECTRICAL ROUTINE Powertrain Control System
·
Electrical inputs/outputs,
vehicle wiring harnesses, PCM,
shift solenoids, digital TR
sensor ·
Carry out Self- Test. Refer to the Powertrain
Control/Emissions Diagnosis (PC/ED) manual for diagnosis
and testing of the Powertrain Control System. Go To Pinpoint Test A or
Go To Pinpoint Test C . Repair as required. Clear
DTCs, road test and repeat Self- Test. 316 —
HYDRAULIC/MECHANICAL ROUTINE Shift Linkage, Cable, Digital TR
Sensor
·
Damaged or incorrectly
adjusted ·
Inspect and repair as required. Verify transmission shift cable
adjustment; refer to Section 307 - 05 . Adjust transmission shift
cable as necessary. After repairing transmission shift cable,
verify that the digital TR sensor is correctly adjusted. Adjust
the digital TR sensor as necessary. Incorrect Pressures
·
Low reverse clutch pressure,
low reverse band pressure, low
line pressure, low EPC
pressure ·
Check pressure at line and EPC pressure taps; refer to Line
Pressure Chart for specifications. If pressures are low, check
the following components: oil filter and seal assembly, main
controls, reverse clutch assembly and reverse servo
assembly. Fluid Filter and Seal Assembly
·
Plugged or damaged ·
Install a new filter and seal assembly. Klj . 15 ba
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GENERAL PROCEDURES
Spring Lock Couplings
Disconnect
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 may be ignited, resulting in possible personal injury.
WARNING: Fuel in the fuel system remains under high pressure even when the engine is
not running. Before servicing or disconnecting any of the fuel lines or fuel system components,
the fuel system pressure must be relieved to prevent accidental spraying of fuel, causing
personal injury or a fire hazard.
1. Relieve the fuel system pressure. For additional information, refer to Pressure Relief in this
section.
2. Remove the fuel tube clip.
SECTION 310-
00: Fuel System — General Information 2003 Mustang Workshop Manual Special Tool(s)
Disconnect Tool, Spring Lock
Coupling (3/8 inch yellow)
310-
D004 (D87L-9280- A) or
equivalent Disconnect Tool, Spring Lock
Coupling (1/2 inch green)
310-
D005 (D87L-9280- B) or
equivalent
Material Item Specification
SAE 5W-
20 Super Premium
Synthetic Blend Motor Oil
XO- 5W20- QSP or equivalent WSS-
M2C153-
H Klj . 1 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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z
Refrigerant R- 134a must not be mixed with air for leak testing or used with air for any
other purpose above atmospheric pressure. R- 134a is combustible when mixed with high
concentrations of air and higher pressures.
z A number of manufacturers are producing alternative refrigerant products that are
designed to be used instead of R- 134a refrigerant. The use of any unauthorized
substitute refrigerant can severely damage the A/C components. If repair is required, use
only new or recycled refrigerant R- 134a.
CAUTION: To avoid contamination of the A/C system, always observe the following:
z Keep service tools and the work area clean.
z Never open or loosen a connection before discharging the system.
z When loosening a connection, if any residual pressure is evident, allow it to leak out
before opening the fitting.
z Evacuate a system that has been opened to install a new component or one that has
been discharged through leakage before charging.
z Seal an open fitting with a cap or plug immediately after disconnecting a component
from the system.
z Clean the outside of the fittings thoroughly before disconnecting a component from the
system.
z Do not remove the sealing caps from a new component until ready to install.
z Refrigerant oil will absorb moisture from the atmosphere if left uncapped. Do not open
an oil container until ready to use, and install the cap immediately after using. Store the
oil in a clean, moisture- free container.
z Install a new O- ring seal before connecting an open fitting. Coat the fitting and the O- ring
seal with refrigerant oil before connecting.
z When installing a refrigerant line, avoid sharp bends. Position the line away from the
exhaust or any sharp edges that can chafe the line.
z Do not open a refrigerant system or uncap a new component unless it is as close as
possible to room temperature. This will prevent condensation from forming inside a
component that is cooler than the surrounding air.
The manual climate control system heats or cools the vehicle depending on the function selector
switch position and the temperature selected.
zThe function selector switch position determines heating or cooling and air distribution.
z The temperature control setting determines the air temperature.
z The heater blower motor switch (18578) varies the blower motor speed.
Principles of Operation
There are four main principles involved with the basic theory of operation:
zheat transfer
z latent heat of vaporization
z relative humidity
z effects of pressure Heat Transfer Klj . 2 ba
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If two substances of different temperature are placed near each other, the heat in the warmer
substance will transfer to the colder substance.
Latent Heat of Vaporization
When a liquid boils (converts to a gas), it absorbs heat without raising the temperature of the resulting
gas. When the gas condenses (reverts back to a liquid), it gives off heat without lowering the
temperature of the resulting liquid.
Relative Humidity
The amount of moisture (water vapor content) that the air can hold is directly related to the air
temperature. The more heat there is in the air, the more moisture the air can hold. The lower the
moisture content in the air, the more comfortable you feel. Removing moisture from the air lowers its
relative humidity and improves personal comfort.
Effects of Pressure on Boiling or Condensation
As the pressure is increased on a liquid, the temperature at which the liquid boils (converts to a gas)
also increases. Conversely, when the pressure on a liquid is reduced, its boiling point is also reduced.
When in the gas state, an increase in pressure causes an increase in temperature, while a decrease in
pressure will decrease the temperature of the gas.
Compressor Anti-
Slugging Strategy
Liquid refrigerant may accumulate in the A/C compressor under certain conditions. To alleviate
damage to the A/C compressor, compressor anti- slugging strategy (CASS) is utilized.
CASS is initiated only under specific conditions:
zthe ignition is off for more than 8 hours
z the ambient temperature is above -4º C (25ºF)
z battery voltage is above 8.5 volts during engine cranking
When these conditions are present, the powertrain control module (PCM) will activate the A/C control
relay prior to cranking of the engine. The A/C control relay engages the A/C compressor for
approximately 4- 15 A/C compressor revolutions or a maximum of 2 seconds (depending upon vehicle
application), allowing the liquid refrigerant to be pushed from the A/C compressor. CASS is initiated by
the PCM regardless of the function selector switch position or the EATC system settings.
The Refrigerant Cycle
During stabilized conditions (air conditioning system shut down), the refrigerant is in a vaporized state
and pressures are equal throughout the system. When the A/C compressor (19703) is in operation, it
increases pressure on the refrigerant vapor, raising its temperature. The high- pressure and high-
temperature vapor is then released into the top of the A/C condenser core (19712).
The A/C condenser core, being close to ambient temperature, causes the refrigerant vapor to
condense into a liquid when heat is removed from the refrigerant by ambient air passing over the fins
and tubing. The now liquid refrigerant, still at high pressure, exits from the bottom of the A/C
condenser core and enters the inlet side of the A/C evaporator core orifice (19D990).
The A/C evaporator core orifice is the restriction in the refrigerant system that creates the high
pressure buildup upstream of the A/C evaporator core (19860) and separates the high and low
pressure sides of the A/C system. As the liquid refrigerant leaves this restriction, its pressure and
boiling point are reduced.
The liquid refrigerant is now at its lowest pressure and temperature. As it passes through the A/C Klj . 3 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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