The Trionic T5.2, an advanced

engine management system An engine control unit (ECU), also commonly called an engine control module (ECM), is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure optimal engine performance. It does this by re ...

in the Trionic series, was introduced in Saab 9000 year 1993 and was discontinued the same year. This engine management system was used on the "long block" engines. It was superseded by the

Trionic T5.5 Trionic T5.5 is an engine management system in the Saab Trionic range. It controls ignition, fuel injection and turbo boost pressure. The system was introduced in the 1993 Saab 9000 2.3 Turbo with B234L and B234R engine. Changes Since 1994 a numb ...

engine management system.

Features

Its

Engine Control Unit An engine control unit (ECU), also commonly called an engine control module (ECM), is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure optimal engine performance. It does this by re ...

is based on a Motorola 32 bit

CPU A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and ...

. The Trionic T5.2 uses a Mecel patented ion-current measurement¹ to decide which cylinder was in the compression phase and had just ignited the air/fuel mixture. The ion-current measurement is thus used to synchronise the ignition's firing of the spark plug with the cylinder which is full of compressed air/fuel. This ion-current measurement can also determine whether there had been detonation or knocking when the cylinder fired. Finally, the ion-current measurement can be used to identify a misfire with outstanding accuracy. Trionic T5.2 uses a MAP (Manifold Absolute Pressure) sensor to, indirectly, measure the weight of the air that has been drawn/forced into the cylinders. It uses a simple slotted aperture disc in conjunction with a crank position sensor to identify the Top Dead Center (TDC) for cylinders 1 & 4 and also to measure the engine's RPM.

References

Mecel 20 Years
Göteborg, Sweden – September 1, 2002 Saab Trionic Engine control systems Automotive technology tradenames