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The principle of HFM

A significant difference compared to the PMS-engine management system is the use of the air flow meter with a film heater (HFM), instead of the air pressure sensor.

The flow meter of air (B2 / 5) contributes to more accurate fuel metering. The principle of operation of airflow measurement: heated by electricity sensor plate (70/1) is cooled by flowing past the intake air.

To maintain a constant plate temperature sensor, the heating current varies in accordance with the density and temperature of intake air. On the basis of fluctuations of the heating current control unit determines the mass of intake air and accordingly adjusts the amount of fuel injected. (70/4 - protective grille.)

The valve injectors are controlled by one in accordance with the working cylinders, thanks to even more precise metering of fuel to reconcile with the engine running. Professional term process: sequential injection.

Anti-knock control system is used to determine and establish the optimum moment of ignition of the fuel, even when lower quality. In the case of faulty ignition, the fuel supply to the respective cylinder.

With electrohydraulic actuator body occurs displacement of the intake camshaft relative to the sprocket of the control device. Through the displacement in the direction of late ignition improving the smooth running of the engine at idle or at high speeds increases capacity. The lower and middle range is improved filling valves of cylinders and thus the torque.

6-cylinder engine: to improve the nature of torque at low speeds applicable resonant switching intake line, which depending on the engine speed reroutes the air to the cylinders. To this end an air manifold behind the throttle is divided into two halves fold pneumatically actuated, one air stream is fed by 3 cylinder. The length of the inlet tract at low speeds due to resonance effect provides good filling of the cylinder and consequently high torque. At high speeds doors open to be able to fully exploit the potential of engine power.