Integrated Electronic Ignition (EI) System

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The integrated EI system consists of a crankshaft position (CKP) sensor, coil pack(s), connecting wiring, and PCM. The coil-on-plug (COP) integrated EI system uses a separate coil per spark plug, and each coil is mounted directly onto the plug. The COP integrated EI system eliminates the need for spark plug wires, but does require input from the camshaft position (CMP) sensor. Operation of the components are as follows:

NOTE: Electronic ignition engine timing is entirely controlled by the PCM. Electronic ignition engine timing is NOT adjustable. Do not attempt to check base timing. You will receive false readings.

The CKP sensor is used to indicate the crankshaft position and speed by sensing a missing tooth on a pulse wheel mounted to the crankshaft. The CMP sensor is used by the COP integrated EI system to identify top dead center of compression of cylinder 1 to synchronize the firing of the individual coils.
The PCM uses the CKP signal to calculate a spark target and then fires the coil pack(s) to that target shown. The PCM uses the CMP sensor, not COP integrated EI systems to identify top dead center of compression of cylinder 1 to synchronize the firing of the individual coils.
The coils and coil packs receive their signal from the PCM to fire at a calculated spark target. Each coil within the pack fires 2 spark plugs at the same time. The plugs are paired so that as one fires during the compression stroke the other fires during the exhaust stroke. The next time the coil is fired the situation is reversed. The COP system fires only one spark plug per coil and only on the compression stroke.
The PCM acts as an electronic switch to ground in the coil primary circuit. When the switch is closed, battery positive voltage (B+) applied to the coil primary circuit builds a magnetic field around the primary coil. When the switch opens, the power is interrupted and the primary field collapses inducing the high voltage in the secondary coil windings and the spark plug is fired. A kickback voltage spike occurs when the primary field collapses. The PCM uses this voltage spike to generate an ignition diagnostic monitor (IDM) signal. IDM communicates information by pulse width modulation in the PCM.
The PCM processes the CKP signal and uses it to drive the tachometer as the clean tach out (CTO) signal.

Fig 1: Identifying Integrated Electronic Ignition System

Courtesy of FORD MOTOR CO.

Fig 2: Six Cylinder Integrated Electronic Ignition (EI) Waveforms - 4, 8, And 10-Cylinder Are Similar

Courtesy of FORD MOTOR CO.