Trionic

Trionic is an engine management system developed by Saab Automobile. It consists of an engine control unit (ECU) that controls 3 engine aspects:

  1. Ignition timing
  2. Fuel injection
  3. Acts as a boost controller.

The numerical prefix 'tri-' yes (Tri being three) in Trionic. 'Ion' comes from the fact that it uses ion current, measured by the spark plugs between combustion events which acts as a sensor for knock, misfire and synchronization detection. The ion current stream which was developed within the ion sensing system due to combustion can be deduced by monitoring the secondary current of the ignition coil. Using the value and wave shape of the current, after the actual spark event, the quality of the actual combustion process is determined, thus allowing the engine control unit to optimize the timing of the spark for the best engine performance while keeping emissions low on a much wider range of rpms.

Since Trionic 7, the throttle and thereby the air charge has also been electronically controlled, but the name "Trionic" was not changed accordingly as it was determined that the name had value.