Slow engine torque control

Fig 1: Engine Torque Control Diagram

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Slow engine torque control is used when driving under constant load, i.e. when the load does not vary or varies slowly. In this case, ECM operates mainly with throttle area to regulate the engine torque.

For higher torque requirements, turbo control will also be used to increase the air mass in the engine so that it produces the requested engine torque.

Fig 2: Engine Torque Control - Communication Diagram

Courtesy of SAAB-SCANIA OF AMERICA, INC.