Genuine OEM Audi Air Mass Meter Sensor, part number 420133471. This vital electronic sensor is responsible for precisely measuring the mass flow rate of air entering the engine's intake system. The data it provides is critical for the engine control unit (ECU) to calculate the correct amount of fuel to inject, ensuring optimal air-fuel mixture, efficient combustion, and reduced emissions. This compact sensor weighs 0.0655 kg and measures 0.091m x 0.045m x 0.039m. Choosing a genuine OEM air mass meter sensor guarantees accurate calibration and signal characteristics, which are essential for maintaining factory engine performance, fuel economy, and emissions compliance.