An exhaust gas treatment system includes a particulate filter to collect particulate matter from exhaust gas flowing therethrough. A regeneration module performs a regeneration operation that regenerates the particular filter. The regeneration operation generates an exothermic event which heats the particulate filter above a target temperature that burns the particulate matter. At least one temperature sensor is disposed adjacent the particular filter to determine at least one temperature of the exhaust gas. The exhaust gas treatment system further includes a temperature diagnostic module to determine a temperature profile of the particulate filter based on the temperature of the exhaust gas. The temperature diagnostic module further determines a temperature deviation of the particulate filter based on a comparison between the temperature profile and a target temperature. The temperature diagnostic module diagnoses the regeneration operation based on a plurality of temperature deviations and a selected time period.