A significant difference compared to the PMS engine management system is the use of an air mass meter with film heater (HFM) instead of an air pressure sensor.
Air mass meter (B2/5) contributes to even more precise dosing of fuel. Functional principle of air flow measurement: electrically heated sensor plate (70/1) cooled by the intake air flowing past.
In order to keep the temperature of the sensor plate constant, the heating current changes according to the density and temperature of the intake air. Based on the fluctuations in the heating current, the control device determines the mass of intake air and regulates the amount of injected fuel accordingly. (70/4 - protective grille.)
The valve injectors are controlled one after the other in accordance with the firing order of the cylinders, thanks to which the fuel dosing can be adjusted even more precisely to the corresponding engine operating conditions. Professional process term: sequential injection.
The anti-knock control system is used to determine and establish the optimum ignition point of the fuel, even with its lower quality. In the event of a malfunction in the ignition system, the fuel supply to the corresponding cylinder is cut off.
With the help of an electro-hydraulic actuator, the intake camshaft is shifted in relation to the sprocket of the control device. By shifting in the retard direction, the smooth running of the engine is improved when idling, or at high speeds it increases power. In the lower and middle valve ranges, the filling of the cylinders and thus the torque are improved.
6-cylinder engine: to improve the torque character at low speeds, a resonant switching intake gas line is used, which, depending on the engine speed, changes the air route to the cylinders. To do this, the air manifold behind the throttle valve is divided into two halves by a pneumatically actuated flap: one air flow is supplied to 3 cylinders respectively. The length of the intake tract at low speeds, thanks to the resonance effect, ensures good cylinder filling and, consequently, high torque. At high speeds, the leaf opens in order to be able to fully utilize the potential of the motor's power.