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Home >> Saab >> 2004 >> 9-3 Linear, Automatic >> Repair and Diagnosis >> Engine Performance >> TRIONIC T8 Fuel Control System >> Technical Description >> Brief description >> Overview
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Brief description: Overview

Saab Trionic T8 was developed by Saab and is a highly advanced engine control system. The main task of the ECM is to control the air mass, fuel and ignition.

When the driver presses the accelerator pedal, a pedal position sensor integrated into the pedal is activated.

This information, in the form of a voltage, is connected to the ECM which converts the voltage value into a torque request from the driver.

The torque request is then processed by the ECM with regard to the prevailing operating conditions and restrictions, and the result is an air mass request to achieve the torque requested by the ECM. The driver's requested torque can be higher than that requested by the ECM. This could be because e.g. the maximum engine torque is already being supplied at the current operating time, or due to TCS control or knock control.

The ECM controls the throttle area (opening angle) together with the turbo (wastegate) to achieve the correct torque, i.e. air mass per combustion.

The system has the following advantages:

The fuel injection function is sequential and controlled by air mass per combustion and engine speed as the main parameters.

Ignition takes place with individual ignition coils placed on the spark plug concerned. The plug together with the ignition coil and CDM are used to detect combustion and any knocking.

This means that neither a camshaft sensor nor a separate knock sensor are required.

Compared with the earlier Trionic T7 system, the following functions are new: