Trionic is an engine management system developed by Saab Automobile. It consists of an engine control unit (ECU) that controls 3 engine aspects: Ignition timing Fuel injection Acts as a boost controller. The numerical prefix 'tri-' 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. History The SAAB Trionic engine management system was developed for the 9000 and 'New Generation' 900 turbocharged engines. The engine management system was first utilized on the Saab B204 and B234 "H" engines to monitor and control the fuel injection system and turbocharging pressure control. The Trionic 5.2 and 5.5 systems utilized the manifold absolute pressure MAP sensor and the intake air charge temperature sensor to calculate the fuel injection curves, while the Trionic 7 and 8 systems are mass air flow type. Both systems have substantial differences that prevent utilization of components between the two. Generally speaking, engine tuners prefer the easier to work with Trionic 5 systems over the Trionic 7 and 8 which are more restrictive in what can be manipulated within the software. The intellectual rights to the Trionic 5 and 7 systems were sold in 2009 to BAIC, along with the Saab H Engine that it was designed for, as part of Saab's restructuring and transfer of ownership of General Motors to Spyker. Models and ECU information Trionic systems are shortened to indicate their version; for e.g. T5, T7, T8, etc. The engines with T5 had red direct ignition modules which differentiated them visually from the T7 models which had a black ignition module. The ignition module on both T5 and T7 are an integral ignition coil