Single spark ignition coils – also known as plug shaft/connector ignition coils, rod or pencil coil or smart plug top coil ignition coils – are directly mounted on the spark plug. Normally no ignition cables are required for this (with the exception of double spark ignition coils), whereby high-voltage connectors are required.

In this design, each spark plug has its own ignition coil, which is located directly above the spark plug insulator.This design enables particularly filigree dimensions.Modular, compact, light smart plug top coil ignition coils of the latest generation are especially suited with their space-saving geometry for modern downsized engines. Even though they are more compact than larger ignition coils, they generate greater combustion energy and higher ignition voltage. Innovative plastics and the extremely safe connection technology of the components inside the ignition coil body also ensure an even greater reliability and durability.

Single spark ignition coils can be used in engines with both even and uneven numbers of cylinders. However, the system must be synchronized via a camshaft sensor. Single spark ignition coils generate one ignition spark per power stroke. Ignition voltage losses are the lowest of all ignition systems due to the compact design of the single spark coil / spark plug unit and the absence of ignition cables. Single spark coils enable the largest possible range of ignition angle adjustment. The single ignition coil system supports monitoring of misfiring in the ignition system on both the primary and secondary side. Any problems that occur can thus be saved in the control unit, rapidly read out in the workshop via OBD and specifically rectified.