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Ignition System - TFI-IV: 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.

Fig 1: TFI-IV "Closed Bowl" Ignition System (3.8L Engines)
G54437Courtesy of FORD MOTOR CO.
Fig 2: TFI-IV Ignition System (Except 3.8L Engines)
G54438Courtesy of FORD MOTOR CO.