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Air Flow Meter/Sensor: Description and Operation



Intake System V6 DFI







Air routing from the air cleaner to the electronic throttle was dethrottled for the new 3.6 l V6 DFI engine by use of the new mass air flow sensor HFM 7. This optimized hot-film mass air flow sensor improves the air throughput of the intake system by reducing the intake air resistance. This results in improved cylinder charging.







Hot-film mass air flow sensor HFM 7

- In the measuring tube on the right next to the MAF sensor there is a special air guide element to optimize air flow.
- The flow characteristics of the bypass duct have been optimized compared to the previous HFM 5 model. The vacuum behind the deflection edge draws the partial air flow required to measure the mass air flow into the bypass duct.
- The inert dirt particles are left behind by this fast motion and are returned to the intake air via an elimination bore.
- This means that the dirt particles cannot falsify the measurement result and damage the sensor element.