A vehicle includes an engine having cylinders in fluid communication with an intake air flow, a mass air flow (MAF) sensor positioned with respect to the intake air flow which outputs a pulse train signal describing the frequency of the intake air flow, and a controller. The controller includes a calibrated non-linear conversion curve recorded in memory. The controller executes a method to convert the frequency data into a corresponding mass air flow using the calibrated non-linear conversion curve, determines the instantaneous mass air flow value at each leading or trailing edge of the pulse train signal, and accumulates the instantaneous mass air flow values over a calibrated duration. A time-weighted average of the accumulated mass air flow values is then used to execute a control action. The controller includes a host computer device and memory storing the curve and instructions for executing the method.