The Bosch Mass Air Flow Sensor with Housing (also called an MAF sensor or air mass meter) measures the amount of air entering the engine. It sends that data to the engine control unit (ECU) so the ECU can calculate fuel delivery, keep the air-fuel ratio correct, and support smooth, efficient combustion. Key Features: Supplied with its housing for a straightforward, complete installation Hot-film sensing technology for accurate airflow measurement across a wide range of operating conditions Helps maintain drivability, throttle response, fuel economy and emissions performance Built to meet original equipment specifications for fit, form and function Backed by Bosch's long experience as an original equipment supplier to automakers worldwide A failing mass air flow sensor can cause rough idle, hesitation, stalling, poor fuel economy or a check engine light. Replacing it with a Bosch unit helps restore proper engine management and performance. Choose the specific part number that matches your application from the options listed on this page.