Coil On Plug

Coil On Plug (COP) ignition operates similar to a standard coil pack ignition except each spark plug has one coil per spark plug. See Fig 1. COP has 3 different modes of operation:

• Engine Cranking
  
  During engine cranking, PCM will fire 2 spark plugs simultaneously. One spark plug will fire on compression stroke and the other spark plug fires on exhaust stroke. Both spark plugs will fire until camshaft position is identified by a successful camshaft sensor signal.
• Engine Running
  
  Once camshaft position is identified and engine is running, only spark plug with cylinder under compression will be fired.
• CMP Failure Mode Effects Management (CMP FMEM)
  
  During CMP FMEM, COP ignition operates similar to engine cranking mode. This allows engine to operate without requiring PCM to know if cylinder is on compression or exhaust stroke.

Fig 1: View Of Coil On Plug

Courtesy of FORD MOTOR CO.