Multiple spark ignition

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The basis for multiple spark ignition is repeated switching on and off of the ignition coil. As a result, the actual ignition spark is extended to produce a band of sparks. The individual sparks can be cancelled by recharging early with the result that no further energy at the spark plug is transmitted to the fuel-air mixture. Residual energy is left In the ignition coil which minimizes the recharging time.

Multiple spark ignition is only intended to be used in the low engine speed range and also during the warm-up phase (spark plug cleaning).

The point at which the spark combustion period of 0.5 milliseconds occurs is determined so that the subsequent sparks can still be discharged before top dead center. This provides a further option for ignition of the fuel-air mixture if combustion is delayed due to unfavorable preconditions.

Follow-up sparking also performs another important function by cleaning the spark plug as it is preconditioned more effectively for the next combustion cycle when several sparks are discharged.