A dosing module for a vehicle comprises a base dose module, a dose adjustment module, and a dose determination module. The base dose module generates a base dose signal that corresponds to a mass flow rate of a dosing agent. The dose adjustment module receives an ammonia (NH3) signal and determines a first dose adjustment based upon the NH3 signal. The NH3 signal indicates NH3 measured downstream of a catalyst. The dose determination module generates a dosing signal based upon the base dose signal and the first dose adjustment.