Located between the engine and the air filter, the mass air flow (MAF) sensor measures the volume and density of air entering the engine. A failing mass air flow sensor can result in sluggish performance, rough idle, poor fuel economy, an illuminated Check Engine light, or possibly a failed emissions inspection. The good news is that it's easily accessible on most vehicles. Shop Advance Auto Parts' inventory of MAF sensors–with trusted brands like Carquest®, ACDelco®, DENSO®, Cardone® and more, we're sure to have one for your ride.