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.
Place transmission in Neutral. Disconnect TFI wiring harness connector. Attach TFI Ignition Tester (105-000003). 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.

Remove TFI module from distributor. Using an ohmmeter, ensure all circuit resistance values are correct. See Fig 1. Refer to the TFI MODULE CIRCUIT RESISTANCE SPECIFICATIONS table. If readings are incorrect, replace TFI module. If readings are correct, check stator for open winding or short to ground. See appropriate COMPONENT article in the ENGINE PERFORMANCE section.

Fig 1: TFI Ignition Module Connector Terminal Identification

Courtesy of FORD MOTOR CO.

TFI MODULE CIRCUIT RESISTANCE SPECIFICATIONS

TFI Terminals ⁽¹⁾

Ohms

Ground Pin - PIP

More than 500

Power Pin - PIP Input Pin

Less than 2000

Power Pin - TFI Power

Less than 200

Ground Pin - Ignition Ground

Less than 2

PIP Input Pin - PIP

Less than 200

⁽¹⁾	See Fig 1 for terminal identification.

If 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 now present, verify coil secondary wire resistance is no greater than 7000 ohms per foot and replace ignition coil.
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.

Fig 2: TFI System Schematic (W/O Computer Controlled Dwell)
Courtesy of FORD MOTOR CO.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Spark Check

Use the Manual With the Right Hardware

When to See a Mechanic

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