2003 FORD MUSTANG check engine

2. Start engine and check line pressures. Refer to the Line Pressure Chart to determine if line
pressure is within specification.
a EPC readings will vary due to EEC strategy. These values are approximate pressures. Actual clutch
apply pressures should be within 69- 103 kPa (10-15 psi) of line pressure. For additional information on
testing, refer to the Clutch Pressure Test in this section. Line Pressure Chart Application Range Idle WOT Stall
EPC Line Pressure EPC Line Pressure
4.6L P, N, OD,
2, 1 207-
276 kPa
(30- 40 psi) 552-
689 kPa (80-
100 psi) 689-
758 kPa
(100- 110 psi) 1310-1448 kPa
(190- 210 psi) 4.6L R 13-
82 kPa (2-
12 psi) 441-
683 kPa (64-
99 psi) 572-
655 kPa
(83- 95 psi) 1427-
1855 kPa
(207- 269 psi) 3.8L P, N, OD,
2, 1 138-
207 kPa
(20- 30 psi) 448-
586 kPa (65-
85 psi) 689-
758 kPa
(100- 110 psi) 1310-1448 kPa
(190- 210 psi) 3.8L R 103-
172 kPa
(15- 25 psi) 448-
620 kPa (65-
90 psi) 572-
662 kPa
(83- 96 psi) 1427-
1862 kPa
(207- 270 psi)
Clutch Pressure Chart 3.8L Transmission Pressures with TP at 1.5 Volts and Vehicle Speed Above 8 Km/h (5 MPH)
Gear EPC Tap
a Line Pressure
Tap Forward Clutch
Tap Intermediate
Clutch Tap Direct Clutch
Tap M1 172-
241 kPa
(25-35 psi) 517-
655 kPa (75-
95 psi) 448-
586 kPa (65-
85 psi) 0-
34 kPa (0-5 psi) 0-
34 kPa (0-5
psi) M2 103-
241 kPa
(15-25 psi) 413-
551 kPa (60-
80 psi) 344-
482 kPa (50-
70 psi) 393-
517 kPa (55- 75
psi) 0-
34 kPa (0-5
psi) 1 172-
241 kPa
(25-35 psi) 517-
655 kPa (75-
95 psi) 448-
586 kPa (65-
85 psi) 0-
34 kPa (0-5 psi) 0-
34 kPa (0-5
psi) 2 103-
241 kPa
(15-25 psi) 413-
551 kPa (60-
80 psi) 358-
468 kPa (52-
68 psi) 379-
517 kPa (55- 75
psi) 0-
34 kPa (0-5
psi) 3 137-
206 kPa
(20-30 psi) 413-
517 kPa (60-
75 psi) 413-
517 kPa (60-
75 psi) 413-
551 kPa (60- 80
psi) 379-
517 kPa
(55- 75 psi) 4 172-
241 kPa
(25-35 psi) 517-
655 kPa (75-
95 psi) 0-
34 kPa (0- 5
psi) 482-
620 kPa (70- 90
psi) 448-
586 kPa
(65- 85 psi)
Clutch Pressure Chart 4.6L Transmission Pressures with TP at 1.5 Volts and Vehicle Speed Above 8 Km/h (5 MPH)
Gear EPC Tap
a Line Pressure
Tap Forward Clutch
Tap Intermediate
Clutch Tap Direct Clutch
Tap M1 172-
241 kPa
(25-35 psi) 517-
655 kPa (75-
95 psi) 448-
586 kPa (65-
85 psi) 0-
34 kPa (0-5 psi) 0-
34 kPa (0- 5
psi) M2 103-
241 kPa
(15-25 psi) 413-
551 kPa (60-
80 psi) 344-
482 kPa (50-
70 psi) 393-
517 kPa (55- 75
psi) 0-
34 kPa (0- 5
psi) 1 172-
241 kPa 517-
655 kPa (75- 448-
586 kPa (65- 0-
34 kPa (0-5 psi) 0-
34 kPa (0- 5 Klj . 2 ba
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a
EPC readings will vary due to EEC strategy. These values are approximate pressures. Actual clutch
apply pressures should be within 69- 103 kPa (10-15 psi) of line pressure. For additional information on
testing, refer to the Clutch Pressure Test in this section.
3. Place the ignition switch in the OFF position. If line pressure is not within specification, check EPC pressure.
4. Connect pressure gauge to EPC pressure tap.
5. Start engine and check EPC pressure. Use the line pressure chart for specifications.
6. If EPC pressure is not within specification, Go To Pinpoint Test E to diagnose EPC operation. If
EPC operation is OK, see the line pressure diagnosis chart for line pressure concern causes. (25-
35 psi) 95 psi) 85 psi) psi)
2 103-
241 kPa
(15-25 psi) 413-
544 kPa (60-
79 psi) 344-
482 kPa (50-
70 psi) 379-
517 kPa (55- 75
psi) 0-
34 kPa (0- 5
psi) 3 172-
241 kPa
(25-35 psi) 517-
655 kPa (75-
95 psi) 372-
579 kPa (54-
84 psi) 482-
613 kPa (70- 89
psi) 379-
586 kPa
(55-85 psi) 4 241-
310 kPa
(35-45 psi) 620-
758 kPa (90-
110 psi) 0-
34 kPa (0-5
psi) 586-
730 kPa (85-
105 psi) 551-689 kPa
(80-100 psi)
Line Pressure Diagnosis Chart Test Results Possible Source
High At Idle —
In All
Positions ·
Wiring Harnesses ·
Run Quick Test. Refer to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual. ·
EPC Solenoid ·
Main Regulator Valve Low At Idle —
In All
Positions ·
Low Fluid Level ·
Control Bodies ·
Leakage in Pump ·
Damaged Gaskets on Separator Valve ·
Damaged Separator Plate ·
Restricted Inlet Filter ·
Case Bolts ·
Loose Main Control Valve Body ·
EPC Solenoid O- Ring ·
EPC Solenoid Bracket ·
Case ·
Sticking Main Regulator Valve ·
Damaged Inlet Tube Seal on Inlet Filter Low In Park Only ·
Valve Body ·
Low/Reverse Servo Low In Reverse Only ·
Separator Plate ·
Low/Reverse Servo or Valve Bodies Klj . 3 ba
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Stall Speed Test
WARNING: Apply the parking brake firmly while carrying out each stall test.
CAUTION: Carry out line pressure test prior to carrying out stall test. If the line pressure is
low at stall, do not carry out stall test or further transmission damage will occur.
The stall speed test checks:
zthe torque converter clutch operation and installation.
z the holding ability of the forward clutch.
z the reverse clutch (the low- reverse bands).
z the planetary one- way clutch.
z the engine driveability.
Conduct this test with the engine coolant and transmission fluid at correct levels and at normal
operating temperature.
Apply the parking brake firmly for each stall speed test. 1. Find the specified stall rpm for the vehicle; see the stall speed diagnosis chart. Use a grease pencil to mark the rpm on the dial of a tachometer.
2. Connect a tachometer to the engine.
3. NOTE: If the rpm recorded by the tachometer exceeds the maximum limits, release the
accelerator pedal immediately because clutch or band slippage is indicated.
In each of the following ranges (D), 2, 1, R, press the accelerator pedal to the floor and hold it ·
Reverse Clutch Low In Neutral Only ·
Valve Body Low In Overdrive Only ·
Forward Clutch ·
Valve Body Low In 1st Position Only ·
Forward Clutch ·
Valve Body ·
Low/Reverse Servo Low In 2nd Only ·
Intermediate Clutch ·
Valve Bodies ·
Forward Clutch Stall Speed
Application Min. Max.
3.8L engine 2,240 2,619
4.6L 2V engine 2,339 2,738
4.6L 4V MACH 1 engine 2,375 2,767 Klj . 4 ba
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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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a
Carry out electrical routine first.
Diagnostic Routines Engagement Concerns
No Forward 201 301
No REVERSE 202 302
Harsh REVERSE 203 303
Harsh Forward 204 304
Delayed/Soft Reverse 205 305
Delayed/Soft Forward 206 306
Shift Concerns
Some/All Shifts Missing 210 310
Timing Concerns
—
Early/Late 211 311
—Erratic/Hunting 212 312
Feel
—
Soft/Slipping 213 313
—
Harsh 214 314
No 1st Gear, Engages in Higher Gear 215 315
No Manual 1st Gear 216 316
No Manual 2nd Gear 217 317
Torque Converter Operation Concerns
No Apply 240 340
Always Applied/Stalls Vehicle 241 341
Cycling/Shudder/Chatter 242 342
Other Concerns
No Engine Braking in 2nd Gear, Manual 2nd or Manual 1st
Position 250 350
Gearshift Lever Efforts High 251 351
External Leaks 252 352
Vehicle Driveability Concerns 253 353
Noise/Vibration in Forward or Reverse 254 354
Engine Will Not Crank 255 355
No PARK (P) Range 256 356
Overheating 257 357
Engagement Concern: No Forward Possible Component Reference/Action
201 —
ELECTRICAL ROUTINE ·
No Electrical Concerns 301 —
HYDRAULIC/MECHANICAL ROUTINE Fluid
·
Incorrect level ·
Adjust fluid to correct level. ·
Condition ·
Inspect as under Fluid Condition Check; refer to Verification of Klj . 3 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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·
Gasket damaged ·
Inspect for damage and install a new gasket. ·
EPC solenoid stuck or
damaged ·
Inspect for damage, contamination. Carry out EPC test in Routine
No. 203. Repair as required. Low Reverse Servo
·
Seals (piston and cover)
damaged ·
Inspect for damage. Repair as required. ·
Servo cover retaining ring
assembled incorrectly ·
Anchor pins (case)
damaged Pump Assembly
·
Bolts not tightened to
specifications ·
Tighten bolts to specifications. ·
Porosity/cross leaks ·
Inspect pump assembly. Install new as required. ·
Gasket damaged ·
Inspect for damage and install a new gasket. ·
No. 1 and No. 2 seal rings
damaged ·
Inspect for damage. Repair as required. Reverse Clutch Assembly
·
Seals, piston damaged ·
Inspect for damage. Repair as required. ·
Check ball missing or
damaged ·
Friction elements
damaged, worn ·
Return spring piston
damaged, worn Low Reverse Band
·
Band, servo, anchor pin
damaged or worn ·
Inspect for damage. Repair as required.
Engagement Concern: Harsh Forward Possible Component Reference/Action
204 —
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 and EPC
test. 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. 304 —
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 ·
Repair as required. Klj . 7 ba
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