2003 FORD MUSTANG engine

PINPOINT TEST E: OUTPUT SHAFT SPEED (OSS) SENSORS
Test Step Result / Action to Take
NOTE:
Refer to the Output Shaft Speed (OSS) Sensor Harness Connector illustration preceding
these pinpoint tests. E1 ELECTRONIC DIAGNOSTICS
z
Check to make sure the transmission harness
connector is fully seated, pins are fully engaged in
connector and in good condition before proceeding.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool: Diagnostic Data Link.
z Enter the following diagnostic mode on the diagnostic
tool: PCM.
z Select PID/Data Monitor and Record.
z Select the PID OSS.
z Does vehicle enter PID/Data Monitor and Record? Yes
GO to
E2 .
No
REPEAT procedure to ENTER
PID. If vehicle did not enter PID,
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual for diagnosis of
PCM. E2 DRIVE CYCLE TEST
z
While monitoring the OSS Speed PID, drive the
vehicle so that the transmission upshifts and
downshifts through all gears.
z Does the OSS Speed PID increase and decrease
with engine and vehicle speed? Yes
CLEAR all DTCs. ROAD TEST to
verify if concern is still present. If
concern is still present, REFER to
Diagnosis By Symptom
in this
section.
No
If the OSS Speed PID does not
increase and decrease with
engine and vehicle speed,
INSPECT for open or short in
vehicle harness, sensor, a PCM
concern, or internal hardware
concern.
If the sensor signal is erratic,
INSPECT for intermittent concern
in the internal/external harness,
sensor, or connector.
If the sensor signal is steady, GO
to E3 .
E3 CHECK RESISTANCE OF OSS SENSOR
z
Disconnect the vehicle harness connector from the
OSS sensor.
z Measure the resistance between the OSS sensor pins. Yes
REFER to
Diagnosis By Symptom for concern diagnosis.
No
INSTALL a new OSS sensor. Klj . 20 ba
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DIAGNOSIS AND TESTING
Special Testing Procedures
The special tests are designed to aid the technician in diagnosing the hydraulic and mechanical portion
of the transmission.
Engine Idle Speed Check
Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual for diagnosis and testing of the
engine idle speed.
Line Pressure Test
CAUTION: Carry out the line pressure test prior to carrying out the stall speed test. If the
line pressure is low at stall, do not carry out stall speed test or further transmission damage
will occur. Do not maintain WOT in any transmission range for more than five seconds.
This test verifies that the line pressure is within specification.
1. Connect pressure gauge to line pressure tap.
SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Item Part Number Description
1 — Direct clutch pressure tap
2 — Forward clutch pressure tap
3 — Electronic pressure control (EPC) pressure tap
4 — Intermediate clutch pressure tap
5 — Line pressure tap Klj . 1 ba
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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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just long enough to let the engine get to wide open throttle (WOT). While making this test, do
not hold the throttle open for more than 5 seconds at a time.
4. Note the results in each range.
5. After each range, move the shift control selector lever to NEUTRAL and run the engine at 1,000 rpm for about 15 seconds to cool the torque converter before making the next test.
6. Refer to the stall speed diagnosis chart for corrective actions.
Air Pressure Tests
Transmission Air Test Plate Stall Speed Diagnosis Chart Selector
Position
Stall Speeds High Stall Speeds Low
(D) Planetary One-
Way Clutch (D), 2 and 1 Forward Clutch or Intermediate
Clutch
(D), 2, 1 and
R Carry Out Pressure Test Torque Converter Stator One-
Way Clutch or
Engine Driveability Concerns R Reverse Clutch or Low Reverse
Band or Servo
Item Part Number Description
1 — Converter bypass
2 — Direct clutch
3 — Forward clutch
4 — 2-
3 accumulator, top 5 — 2-
3 accumulator, bottom 6 — Reverse servo
7 — Overdrive servo, apply
8 — Overdrive servo, release
9 — Intermediate clutch
10 — Reverse clutch
11 — 1-
2 accumulator, apply Klj . 5 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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Fluid Leakage in Torque Converter Area
In diagnosing and correcting fluid leaks in the front pump support and gear and torque converter area,
use the following procedures to locate the exact cause of the leakage. Leakage at the front of
transmission, as evidenced by fluid around the torque converter housing, may have several sources.
By careful observation it is possible, in many instances, to pinpoint the source of leak before removing
the transmission from the vehicle. The paths which the fluid takes to reach the bottom of the torque
converter housing are shown in the illustration. The five steps following correspond with the numbers
in the illustration.
1. Fluid leaking by the front pump seal lip will tend to move along the impeller hub and onto the back of the impeller housing. Except in the case of a total seal failure, fluid leakage by the lip of
the seal will be deposited on the inside of the torque converter housing only, near the outside
diameter of the housing.
2. Fluid leakage by the outside diameter of the front pump seal and front pump body will follow the same path that leaks by the inside diameter of the front pump seal follow.
3. Fluid that leaks by a front pump to case bolt or pump gasket will be deposited on the inside of the torque converter housing only. Fluid will not be deposited on the back of the torque
converter.
4. Fluid leakage from the converter drain plug, (model dependent) converter seal weld or converter to flexplate stud weld will appear at the outside diameter of the torque converter on the back
face of the flexplate and in the converter housing only near the flexplate. Fluid leaks from the
torque converter will leave a ring of fluid around the inside of the torque converter housing.
5. NOTE: White facial tissue paper may aid in determining the color (red is transmission fluid) and
source of the leaking fluid.
Engine oil leaks are sometimes incorrectly diagnosed as transmission pump gasket leaks. The 22 7D273 Fluid tube connector
23 87650-S2 Converter drain plug Klj . 3 ba
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