Double spark ignition coils produce for every two spark plugs / two cylinders each an optimum ignition voltage in different cylinders. The voltage is distributed so that.
● The air / fuel mixture of a cylinder is ignited at the end of a compression stroke (ignition time) (primary sparks – powerful ignition spark),
● The other cylinder’s ignition spark jumps in the discharge stroke (secondary sparks – low energy). Double spark ignition coils generate two sparks per crankshaft rotation (primary and secondary spark). No synchronization with the camshaft is required. However, double spark ignition coils are only suitable for engines with even numbers of cylinders. Thus in vehicles with four cylinders and six cylinders, two and three double spark ignition coils respectively are installed.