Ignition System - Tfi-Iv Ford Mustang III рестайлинг

DESCRIPTION

All EEC-IV controlled engines use the TFI-IV ignition system. The TFI-IV distributor is a gear driven, die cast unit. A Hall Effect stator assembly is used to trigger the ignition coil. This distributor does not use conventional centrifugal/vacuum advance mechanisms. (Scheme 1)or (Scheme 2). On models with 3.8L engines, a "closed bowl" distributor is used. The TFI ignition module is mounted on the cowl behind the engine (Continental, Sable and Taurus) or the radiator crossmember (Cougar and Thunderbird). On all others, the TFI ignition module is integrally mounted on base of distributor.

The TFI ignition module used on manual transaxle equipped vehicles features a push start mode. This feature allows vehicle to be push started if necessary. An "E" core ignition coil is used.

OPERATION

The TFI-IV distributor uses a Hall Effect switch mechanism to switch primary voltage and send a Profile Ignition Pickup (PIP) to the Electronic Control Assembly (ECA) and TFI module on 3.8L engines. On all models, the ECA uses PIP input signal to produce an output signal called SPOUT that is sent to the TFI ignition module to be used to trigger discharge of coil secondary voltage.

Secondary voltage is distributed through a conventional cap, rotor and spark plug wires.

Scheme 1

Scheme 2

TESTING

PRELIMINARY STEPS

1. Visually inspect engine compartment to ensure that all vacuum hoses and spark plug wires are properly routed and securely connected. Examine all wiring harnesses and connectors for insulation damage, burnt or overheated wires, and loose or broken terminals.
2. Ensure that battery is fully charged and that all accessories are off. Check that TFI ignition module is securely fastened to distributor base. Obtain Spark Tester (D81P-6666-A). (Scheme 3) A spark plug with a broken side electrode is NOT recommended as it may lead to incorrect results.
3. When inspecting wiring harness, both a visual inspection and a continuity check should be performed. When checking continuity perform a "WIGGLE" test to assist in finding intermittent faults.

Scheme 3

Crank Mode

1. Connect Spark Tester (D81P-6666-A) between ignition coil wire and engine ground. Crank engine while checking for spark at tester. If spark occurs, inspect distributor cap and rotor for damage or carbon tracking.
2. If no spark occurs, remove distributor cap and crank engine to ensure distributor shaft rotates. If distributor shaft does not rotate while cranking engine, repair as necessary. If distributor rotates go to STATOR test.

Run Mode

1. Place transmission in Park or Neutral and set parking brake. Disconnect wire at "S" terminal of starter relay and attach remote starter switch.
2. Connect Spark Tester (D81P-6666-A) between ignition coil wire and engine ground. Turn ignition switch to "RUN" position. Using remote starter switch, crank engine while watching for spark at tester. If spark is present, ignition system is okay. If spark was not present, go to next test.

TFI CONNECTOR VOLTAGE CHECK

1. Disconnect wiring harness connector from TFI module. Inspect connector for dirt, corrosion, or damage. Repair if necessary. Disconnect wire at "S" terminal of starter solenoid.
2. Attach negative voltmeter lead to distributor base. Measure voltage at battery. With negative lead of voltmeter still connected to distributor base, check voltages at TFI ignition module wiring harness terminals. See WIRING HARNESS TEST table. (Scheme 4)
3. If all readings are at least 90% of battery voltage, replace TFI module. If any reading is less than 90% of battery voltage, inspect wiring harness and connectors. Also check for a worn or damaged ignition switch. Repair or replace as necessary.

WIRING HARNESS TEST

Scheme 4

3.8L Engines (Test No. 1)

1. Separate harness connector from distributor. Inspect for dirt, corrosion or damage. Measure resistance between terminals No. 1 and 5 on distributor side of stator connector. (Scheme 5)
2. If resistance is more than 5 ohms, replace stator. If resistance is less than 5 ohms, proceed to next step.
3. Measure resistance between stator connector terminal No. 2 and distributor base. Measure resistance between stator connector terminal No. 6 and distributor base. Resistance should be less than one ohm in each case.
4. If resistance is more than one ohm, inspect retaining screws to the stator in the distributor bowl. If screws are okay, replace stator.
5. If resistance is less than one ohm, go to 3.8L ENGINES (TEST NO. 2) under STATOR TESTING.

Scheme 5

3.8L Engines (Test No. 2)

1. Place transmission in Park or Neutral and set parking brake. Disconnect harness connector from TFI module. Using DVOM, attach negative lead to distributor base and positive lead to TFI harness connector terminal No. 6. Disconnect wire at "S" terminal of starter relay and attach remote starter switch.
2. While performing this step the ignition should be in the "RUN" position. Crank engine using remote starter switch while watching DVOM. If DVOM varies between 3-6 volts, stator is okay. Remove remote starter switch. Reconnect wire to starter relay and connector to TFI module.
3. If DVOM did not vary between 3-6 volts during testing in step 2), replace stator. Remove remote starter switch. Reconnect wire to starter relay and connector to TFI module.

Except 3.8L Engines (Test No. 1)

1. Place transmission in Park or Neutral and set parking brake. Disconnect harness connector from TFI module. Using DVOM, attach negative lead to distributor base and positive lead to TFI harness connector terminal No. 6. Disconnect wire at "S" terminal of starter relay and attach remote starter switch.
2. Crank engine using remote starter switch while watching DVOM. If DVOM varies between 3-6 volts, stator is okay. Remove DVOM and remote starter switch. Reconnect wire to starter relay and connector to TFI module.
3. If voltmeter did not vary between 3-6 volts during testing in step 2), remove distributor cap and ensure rotor rotates when engine is cranked. If rotor rotation is okay, remove DVOM and remote starter switch. Reconnect wire to starter relay and connector to TFI module and go to EXCEPT 3.8L ENGINES (TEST NO. 2) under STATOR TESTING.

Scheme 6

1. Remove distributor from engine. Remove TFI ignition module from distributor. Measure resistance between TFI module terminals. (Scheme 6) Refer to TFI MODULE RESISTANCE VALUES table. TFI MODULE RESISTANCE VALUES Measure Between Terminals Ohms "GND"-"PIP In" Greater Than 500 "PIP PWR"-"PIP In" Less Than 2000 "PIP PWR"-"TFI PWR" Less Than 200 "GND"-"IGN GND" Less Than 2 "PIP In"-"PIP" Less Than 200
2. If TFI module resistance readings are correct, replace stator assembly. If any resistance readings are not within specification, replace TFI module.

IGNITION COIL & SECONDARY COIL WIRE

Substitute coil and coil wire with known good parts. Install Spark Tester (D81P-6666-A) between ignition coil wire and engine ground. Crank engine. Turn ignition off. If spark is present, determine if coil and/or secondary wire was cause of no spark

replace part(s) as necessary.

1. Disconnect in-line connector near TFI module. Install Spark Tester (D81P-6666-A) between ignition coil wire and engine ground. Crank engine. Turn ignition off.
2. If spark was present, check PIP-A and ignition ground wires for continuity. Service as necessary. If wires are okay, see appropriate EEC-IV article in COMPUTERIZED ENGINE CONTROL section listed below. If spark was not present, go to next test. «1.9L CEC TESTS W/CODES»(ref-94824) «2.2L SYSTEMS/TESTS W/CODES»(ref-94825) «2.3L CEC TESTS W/CODES»(/ford/mustang/iii-1986-1993/remont/testing-diagnostics/#23l-cec-tests-wcodes) «2.5L CEC TESTS W/CODES»(ref-94827) «3.0L CEC TESTS W/CODES»(ref-94819) «3.8L CEC TESTS W/CODES»(ref-94820) «5.0L CEC TESTS W/CODES»(/ford/mustang/iii-1986-1993/remont/testing-diagnostics/#50l-cec-tests-wcodes) «EEC-IV THEORY/OPERATION»(/ford/mustang/iii-1986-1993/remont/theory-operation/#eec-iv-theoryoperation)

1. Disconnect wiring harness from stator and TFI module. Measure resistance between terminal No. 5 of the stator harness connector and terminal No. 6 of the TFI harness connector. (Scheme 4)and (Scheme 5).
2. If resistance is less than 5 ohms, go to IGNITION COIL SUPPLY VOLTAGE TEST in this article. If resistance is more than 5 ohms. Inspect and service wiring between the distributor and TFI module (PIP-B circuit).

All Others

Disconnect in-line connector near TFI module. Install Spark Tester (D81P-6666-A) between ignition coil wire and engine ground. Crank engine. Turn ignition off. If spark was present, check PIP and ignition ground wires for continuity. Service wiring as necessary. If wires are okay, see appropriate EEC-IV article in COMPUTERIZED ENGINE CONTROL section listed below. If spark was not present, go to IGNITION COIL SUPPLY VOLTAGE test.

1. «1.9L CEC TESTS W/CODES»(ref-94824)
2. «2.2L SYSTEMS/TESTS W/CODES»(ref-94825)
3. «2.3L CEC TESTS W/CODES»(/ford/mustang/iii-1986-1993/remont/testing-diagnostics/#23l-cec-tests-wcodes)
4. «2.5L CEC TESTS W/CODES»(ref-94827)
5. «3.0L CEC TESTS W/CODES»(ref-94819)
6. «3.8L CEC TESTS W/CODES»(ref-94820)
7. «5.0L CEC TESTS W/CODES»(/ford/mustang/iii-1986-1993/remont/testing-diagnostics/#50l-cec-tests-wcodes)
8. «EEC-IV THEORY/OPERATION»(/ford/mustang/iii-1986-1993/remont/theory-operation/#eec-iv-theoryoperation)

IGNITION COIL SUPPLY VOLTAGE

1. Attach negative voltmeter lead to distributor base. Measure voltage at battery. Place ignition switch in "RUN" position. Measure voltage at coil positive terminal. Turn ignition off. If reading was 90% of battery voltage, go to TFI SUPPLY VOLTAGE test.
2. If reading is less than 90% of battery voltage, inspect wiring harness between ignition coil and ignition switch for an open and also check for a worn or damaged ignition switch. When testing is complete, reconnect ignition module harness connector. Repair or replace parts as necessary.

3.8L Engines

1. Disconnect wire at "S" terminal of starter relay. Attach negative voltmeter lead to distributor base. Measure battery voltage.
2. Following TFI SUPPLY VOLTAGE CHECK table, measure connector terminal voltage using straight pin inserted into connector terminal and turning ignition switch to position shown in table.
3. Turn ignition switch to "OFF" position. Remove straight pin. Reconnect wire to "S" terminal of starter relay. If voltage measured in each case was greater than 90% of battery voltage, go to STATOR SUPPLY VOLTAGE test. If voltage measured in each case was less than 90% of battery voltage, check for faults in wiring harness, connectors or damaged ignition switch.

1. Disconnect wiring harness from TFI module and inspect connector terminals for damage. Disconnect wire at "S" terminal of starter relay. Attach negative voltmeter lead to distributor base. Measure battery voltage.
2. Following TFI SUPPLY VOLTAGE CHECK table, measure connector terminal voltage using straight pin inserted into connector terminal and turning ignition switch to position shown in table. (Scheme 4)
3. Turn ignition switch to "OFF" position. Remove straight pin. Reconnect wire to "S" terminal of starter relay. If voltage measured in each case was greater than 90% of battery voltage, check for faults in wiring between the coil and TFI module terminal No. 2 or any additional wiring or components connected to that circuit.
4. If voltage measured in each case was less than 90% of battery voltage, check for faults in wiring harness, connectors or damaged ignition switch.

TFI SUPPLY VOLTAGE CHECK

3.8L Engine

1. Attach negative voltmeter lead to distributor base. Measure voltage at battery. Place ignition switch in "RUN" position. Measure voltage at terminal No. 8 of harness side of stator connector. Turn ignition off.
2. If reading was 90% of battery voltage, go to TFI WIRING HARNESS test. If reading was less than 90% of battery voltage, check wiring between stator and ignition switch or damaged ignition switch.

1. With wiring harness connected to stator, measure resistance between distributor base and terminal No. 1 of the TFI ignition module harness connector. (Scheme 4)
2. If resistance is less than one ohm, inspect for faults in wiring between coil and TFI module terminal No. 2, or any additional wiring or components connected to that circuit. Repair wiring as necessary.
3. If resistance is more than one ohm, inspect wiring between harness connector at TFI module and harness connector at distributor ground circuit. NOTE: For further testing, see appropriate EEC-IV article in COMPUTERIZED ENGINE CONTROLS section listed below. «1.9L CEC TESTS W/CODES»(ref-94824) «2.2L SYSTEMS/TESTS W/CODES»(ref-94825) «2.3L CEC TESTS W/CODES»(/ford/mustang/iii-1986-1993/remont/testing-diagnostics/#23l-cec-tests-wcodes) «2.5L CEC TESTS W/CODES»(ref-94827) «3.0L CEC TESTS W/CODES»(ref-94819) «3.8L CEC TESTS W/CODES»(ref-94820) «5.0L CEC TESTS W/CODES»(/ford/mustang/iii-1986-1993/remont/testing-diagnostics/#50l-cec-tests-wcodes) «EEC-IV THEORY/OPERATION»(/ford/mustang/iii-1986-1993/remont/theory-operation/#eec-iv-theoryoperation)

Scheme 7

Scheme 8

Removal & Installation (Escort)

Disconnect wiring harness at TFI module. Remove distributor cap and rotor. Remove distributor hold-down bolts. Remove distributor from engine. To install, reverse removal procedure. Ensure distributor coupling engages with camshaft drive. Adjust base ignition timing.

Removal & Installation (Tempo & Topaz)

1. Rotate engine until piston in cylinder No. 1 is at TDC of compression stroke. Mark relative position of No. 1 spark plug wire tower on distributor housing. Disconnect wiring harness at TFI ignition module. Remove distributor cap and rotor.
2. Remove distributor mounting bolt and clamp. Some units may be equipped with security-type hold-down bolts. If this is the case, use Distributor Hold-Down Bolt Wrench (T82L-12270-A) to remove bolt. Remove distributor from engine.
3. To install, reverse removal procedure. Ensure timing marks are aligned on crankshaft pulley. Ensure No. 1 spark plug wire tower aligns with mark on distributor housing. Adjust base ignition timing.

Removal & Installation (Continental, Sable & Taurus)

1. Rotate engine until piston in cylinder No. 1 is at TDC of compression stroke. Mark relative position of No. 1 spark plug wire tower on distributor housing. Disconnect wiring harness at TFI ignition module. Remove distributor cap and rotor.
2. Remove distributor hold-down bolt and clamp. Remove distributor from engine. DO NOT remove intermediate shaft on 2.5L HSC/CFI engine. On 3.0L EFI engine, the intermediate shaft is removed with distributor assembly.
3. To install, reverse removal procedure. Ensure timing marks are aligned on crankshaft pulley. Ensure No. 1 spark plug wire tower aligns with mark on distributor housing. Adjust base ignition timing.

Removal & Installation (All Others)

1. Disconnect wiring harness at TFI ignition module. Remove distributor cap and rotor. Note position of shaft plate, armature, and rotor locating holes. Remove hold-down bolt and clamp. Remove distributor from engine.
2. To install, reverse removal procedure. Ensure that position of shaft plate, armature, and rotor locating holes are in the same position as during removal. Ensure TFI ignition module is properly oriented on engine.

Removal (3.8L Engines)

1. Using a Phillips screwdriver, remove leaf screen attaching screws from top of cowl. Separate engine compartment/cowl seal from leaf screen and cowl dash extension panel near TFI ignition module.
2. Lift screen to allow access to TFI ignition module. Press up on harness connector latch from under TFI module shroud to disconnect harness connector from module. Remove 2 module retaining nuts and washers. Remove TFI ignition module and heat-sink as an assembly.

Installation

1. To install, insert module and heat-sink, with heat-sink facing down, into cowl dash extension to allow nuts to be installed. Install washers.
2. Install and tighten nuts to 44-70 INCH lbs. (5-8 N.m). connect harness connector to module. Install leaf screen. Position seal on leaf screen and cowl dash extension.

1. Remove distributor from engine. With distributor on workbench, remove 2 module mounting screws. Slide right side of module down toward distributor mounting flange, and then back up. Move left side of module down toward distributor mounting flange and then back up.
2. Alternate sliding right and left sides of module until module terminals are disengaged from connector in distributor. Any attempt to pull module from mounting surface prior to moving it toward distributor flange WILL BREAK module electrical connector pins.
3. To install, reverse removal procedure. Apply a 1/32" thick ribbon of Silicone Dielectric Compound (D7AZ-19A331-A) to TFI ignition module base plate. Adjust base ignition timing.

Removal (Escort)

1. Remove distributor. Using a small screwdriver, remove drive coupling spring. Using compressed air, blow dirt and oil away from end of distributor. Mark orientation of drive coupling to shaft.
2. Align drive pin with slot in base. Support distributor and drive pin out with a 3/32" drift and small hammer. (Scheme 9) Remove drive coupling and set aside for reassembly.
3. Ensure shaft is free of nicks or burrs. If burrs are present, polish shaft with emery paper to remove minor burrs. Wipe shaft clean after polishing. Pull up on shaft plate to remove shaft from distributor.
4. Remove screws and TFI ignition module. See TFI IGNITION MODULE REMOVAL & INSTALLATION (ALL OTHERS). Wipe grease from base and module to keep surfaces free of dirt. Remove octane rod retaining screw and octane rod assembly.
5. Remove screws retaining stator connector in distributor bowl. Save screws for installation. Gently pull up on stator to remove from bowl.
6. Inspect base bushing, oil seal, spring retainer, "O" ring, and distributor housing for wear, cracks, or other damage. If necessary, replace spring retainer or "O" ring. If distributor housing, bushing, or oil seal are damaged, replace entire distributor assembly.

Scheme 9

1. Place stator over bushing and press down on seat. Place stator connector in position. Tab should fit in notch of base and fastening eyelets should align with screw holes. Position wires away from moving parts.
2. Install and tighten stator screws. With seal on octane rod, insert rod in holes. Install octane rod through distributor base hole. Place end of rod onto same post as original stator. Install and tighten octane rod screw.
3. Wipe back of TFI ignition module and distributor mounting plate clean. Apply Silicone Dielectric Compound (D7AZ-19A331-A) to back of module and spread evenly.
4. Turn distributor base upside-down so that stator connector is in full view. Insert TFI ignition module, making sure that module pins are inserted into stator connector.
5. Fully seat module into connector and against base. Install and tighten TFI module screws. Lubricate distributor shaft, just below armature, with light oil. DO NOT over lubricate.
6. Insert shaft assembly through base bushing. Place drive coupling over shaft and line up mark made during removal. Start pin into drive coupling and shaft.
7. Support distributor and drive pin into shaft until end of pin is flush with step in drive coupling. Check drive coupling for freedom of movement. Ensure that pin does not extend beyond step in coupling in either direction.
8. Remove distributor from support. Check distributor for freedom of rotation. Install drive coupling spring in groove of drive coupling. Install distributor. Check base timing.

Removal (All Others)

1. Remove distributor from engine. On all except Continental, remove screws and TFI ignition module from distributor. See TFI IGNITION MODULE REMOVAL & INSTALLATION (ALL OTHERS). Wipe grease from base and module to keep surfaces free of dirt.
2. On all models, hold gear and loosen armature screws, DO NOT hold armature. Remove screws and armature. Using a felt tip pen, mark armature and gear for installation reference. Remove and discard roll pin in gear.
3. Place distributor in Axle Bearing Remover (T75L-1165-B). Press off gear using arbor press and Pinion Bearing Cone Remover (D79L-4621-A). Using emery cloth, remove burrs from distributor shaft. Remove shaft from distributor assembly.
4. Remove thrust washer from distributor and save for installation. (Scheme 10) Remove screw and octane rod assembly. Save octane rod and screw for installation. Remove stator assembly screws and stator. Save screws for installation.
5. Inspect base bushing, "O" ring, and distributor housing for wear, cracks, or other damage. If necessary, replace "O" ring. If distributor housing or bushings are worn, replace entire distributor assembly.

Scheme 10

1. Place stator assembly over bushing and press down to seat. Place stator connector in position. Tab should fit in notch of base and fastening eyelets should align with screw holes. Position wires away from moving parts. Install and tighten stator screws.
2. Install octane rod through distributor base hole. Place end of rod onto same post as original stator. Install and tighten octane rod screw. Install thrust washer on top of bushing (if equipped). Lubricate distributor shaft, just below armature, with light oil. DO NOT over lubricate.
3. Install shaft through base bushing. Place a 1/2" deep well socket over shaft, invert assembly and place in arbor press. If distributor uses a screw-down rotor, invert assembly and place in arbor press. Place distributor drive gear on shaft. Align marks made during removal.
4. Place a 5/8" deep well socket over shaft and gear. Press gear until holes align with holes in shaft. If holes do not line up, press gear off and try once more. DO NOT try to align holes using a drift or roll pin.
5. Insert new roll pin through gear and shaft. If armature was removed, install armature. Tighten armature screws. Check distributor for freedom of rotation. If armature contacts stator, replace distributor.
6. Wipe back of TFI ignition module and distributor mounting plate clean. Apply Silicone Dielectric Compound (D7AZ-19A331-A) to back of module and spread evenly.
7. Turn distributor base upside-down so that stator connector is in full view. Insert TFI module. Ensure that module pins are inserted into stator connector.
8. Fully seat TFI ignition module into connector and against base. Install and tighten TFI module screws. (Scheme 10) Install distributor. Check base timing.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• 2.3L CEC TESTS W/CODES
• 5.0L CEC TESTS W/CODES
• EEC-IV THEORY/OPERATION