A mass air-flow sensor is used on fuel-injected vehicles to tell the computer how much air is going into the engine. Discover why a mass air flow sensor must be removed in order to be checked with help from an auto mechanic in this free video on auto parts. Expert: JB Hebert Contact: www.wrxtra.com Bio: JB Hebert is a machinist, metal fabricator, and auto mechanic who has been fixing and modifying all things mechanical for over 20 years. Filmmaker: David Pakman