The computer for correct air/fuel mixture. The computer uses this information for air/fuel. Mixture control, ignition timing and to aid the transmission in pressure control for accurate.Failure Symptoms: Malfunction Indicator Light illumination, failed emission test. Engine hesitation on acceleration, poor fuel economy, poor engine performance, engine no start condition, engine surging. The item "MAS4522 MASS AIR FLOW METER 5 Blades Fits 128I 323I 328I 328XI 528I 528XI X3 X5" is in sale since Saturday, July 22, 2017. This item is in the category "eBay Motors\Parts & Accessories\Car & Truck Parts\Air Intake & Fuel Delivery\Sensors". The seller is "globalsourcewd" and is located in El Monte, California. This item can be shipped worldwide.