An aftertreatment system for treating constituents of an exhaust gas produced by an engine includes a heater configured to selectively heat the exhaust gas entering the aftertreatment system. An aftertreatment component is disposed downstream of the heater. A gas sensor is disposed downstream of the heater and upstream of the aftertreatment component. The gas sensor comprises a sensing element, and a heating element configured to selectively heat the sensing element to an operating temperature of the sensing element.