Patent ID: 8069656

Claim:
A method of controlling an internal combustion engine system comprising an engine, an exhaust system constructed and arranged to flow exhaust gases from the engine therethrough, the exhaust system comprising an oxidation catalyst upstream of a particulate filter, the particulate filter being constructed and arranged to capture particulates in the exhaust gas, and a doser for injecting hydrocarbons into the exhaust gases, the method comprising: determining if the exhaust gas temperature exiting the oxidation catalyst is below a first temperature, and if so, starting a real time accumulator to measure the time lapse since the exhaust gas temperature exiting the oxidation catalyst has fallen below the first temperature, determining if an accumulated time as measured by the real time accumulator has exceeded a first time period, and if so, elevating the temperature of the exhaust gas exiting the oxidation catalyst, wherein elevating the temperature of the exhaust gas exiting the oxidation catalyst occurs after the accumulated time has exceeded a second time period.