22204-21010 2220421010 Mass Air Flow Meter Maf Sensor For Lexus For RX300 RX 300 For Toyota For Land For Cruiser 90 3.4 i For Prius 1.5 Direct replacement for a proper fits and easy installation, the MAF sensor can easily be located beside the air intake box inside the engine bay. It works even better and lasts longer. Function The air mass flow sensor is used to measure the intake air volume and intake temperature of the engine to help control its speed. The air mass sensor accurately determines the mass of air injected by the engine (air flow mass). The air mass sensor's signal is used to compute how much fuel is injected into the engine and, in the case of engines, to regulate how much exhaust is circulated. The MAF sensor accurately measures the air entering the engine, allowing the ECU to optimize the air-fuel ratio for improved engine performance and fuel efficiency.