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Spark Check

  1. Using a high output spark tester, check for spark at coil wire while cranking engine. If spark is present, go to step 2). If spark is not present, remove distributor cap and crank engine to check for distributor rotation. If okay, check coil secondary wire resistance. Resistance should be no greater than 7000 ohms per foot.
  2. Place transmission in Neutral. Disconnect TFI wiring harness connector. Attach TFI Ignition Tester (105-000002). Connect Red lead of tester to 12 volts. Attach remote starter to "S" terminal of starter relay. Crank engine with remote starter while observing 2 LED lights on tester. If the PIP light blinks, go to step 4). If not, remove distributor.
  3. Remove TFI module from distributor. Using an ohmmeter, ensure all circuit resistance values are correct. See TFI CIRCUIT SPECIFICATIONS table. If readings are correct, replace stator. If readings are incorrect, replace TFI module.
    TFI CIRCUIT SPECIFICATIONS

    TFI Terminals Ohms
    GND-PIP More 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
  4. If the TACH light did not blink in step 2), replace TFI module and repeat step 1). If spark is still not present, replace ignition coil and module connector. If the TACH light did blink in step 2), substitute ignition coil with a known working unit and repeat step 1). If spark is present, verify coil secondary wire resistance is greater than 7000 ohms per foot. Replace ignition coil.
  5. If spark was not present in step 4), connect original vehicle coil and spark tester. Remove pin-in-line connector located near distributor. Crank engine while checking for spark. If spark is present, inspect PIP and ignition ground circuits to verify continuity. See Fig 2 and Fig 3 . Repair as necessary.
  6. If spark was not present in step 5), measure battery voltage. Measure voltage at ignition coil positive (+) terminal. Ignition coil positive (+) terminal voltage should be at least 90 percent of battery voltage. If not, check circuitry between ignition coil and ignition switch for wear or damage. Repair as necessary.
  7. If ignition coil positive (+) terminal voltage was at least 90 percent of battery voltage in step 6), remove connector from ignition module. Disconnect starter relay "S" terminal. Turn ignition on. Measure voltage at ignition module connector terminals. See Fig 1 . Voltage should be at least 90 percent of battery voltage.
  8. If not, check circuitry between ignition coil and ignition switch for wear or damage. Repair as necessary. If voltage was at least 90 percent of battery voltage in step 7), inspect wiring between ignition module terminal No. 2 and coil. If okay, check all related circuitry. Replace or repair as necessary.
Fig 1: TFI Ignition Module Connector Terminal Identification
G106319Courtesy of FORD MOTOR CO.
TFI CIRCUIT SPECIFICATIONS

TFI Terminal Ignition Switch Position
With CCD
No. 3 Run & Start
Without CCD
No. 3 Run & Start
No. 4 Start
Fig 2: TFI System Electrical Schematic
G90I09245Courtesy of FORD MOTOR CO.
Fig 3: TFI System With CCD Electrical Schematic
G90A09246Courtesy of FORD MOTOR CO.