2003 FORD MUSTANG low oil pressure

DIAGNOSIS AND TESTING
Leakage Inspection
CAUTION: Do not try to stop the fluid leak by increasing the torque beyond specifications.
This may cause damage to the case threads.
Check the fluid filler tube connection at the transmission case. If leakage is found here, install a new
grommet.
Check the VSS plug or VSS sensor O-ring (model dependent). If leakage is found install a new O- ring.
Check fluid lines and fittings between the transmission and the cooler in the radiator tank for
looseness, wear, or damage. If leakage cannot be stopped by tightening a fluid tube nut, install new
parts. When fluid is found leaking between the case and cooler line fitting, check for missing or
damaged O- ring, then tighten the fitting to maximum specification.
If the leak continues, install a new cooler line fitting and tighten to specification. The same procedure
should be followed for fluid leaks between the radiator cooler and the cooler line fittings in this section;
refer to Section 307 - 02 .
Check the engine coolant in the radiator. If transmission fluid is present in the coolant, the cooler in the
radiator is probably leaking.
The cooler can be further checked for leaks by disconnecting the lines for the cooler fittings and
applying no more than 345 kPa (50 psi) air pressure to the fittings. Remove the radiator cap to relieve
the pressure buildup at the exterior of the oil cooler tank. If the cooler is leaking and or will not hold
pressure, install a new cooler.
If leakage is found at the transmission range selector lever, install a new seal.
If leakage is found at the transmission internal harness connector, install a new O- ring. 4R70W External Sealing SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 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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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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