Air mass flow sensor and motor vehicle

The invention relates to an air mass flow rate sensor for determining an air mass flow rate, comprising a housing (4) and sensor electronics (6), the sensor electronics being arranged at least partially in a housing chamber (8) of the housing (4), wherein the housing (4) has a flow channel (14) for conducting an air mass flow (L) to be measured through the housing (4), the flow channel (14) having a measurement channel (20) for conducting a part of the air mass flow (L) flowing into the flow channel (14) to a measurement point (24) of the sensor electronics (6), and a bypass channel (22), the bypass channel (22) branches off a portion of the air mass flow (L) flowing into the flow channel (14) before reaching the measuring point (24) and discharges the portion of the air mass flow from the housing (4). Wherein a first wall element (28) separating the bypass channel (22) and the measuring channel (2) at least in sections has a wall height (H1) which is reduced at least in sections such that the first wall elem