Provided are methods for warming up a vehicle exhaust treatment system prior to an engine start, wherein the vehicle includes an internal combustion engine (ICE), a supercharger capable of delivering air to an ICE intake, an exhaust gas treatment system including an exhaust gas treatment device and an upstream electric heating device and capable of accepting exhaust gas from the ICE, and optionally a turbocharger having a turbine in fluid communication with the exhaust gas treatment system. Methods include establishing fluid communication between the supercharger and the exhaust gas treatment system, engaging the supercharger to communicate air to the exhaust gas treatment system via the supercharger, and engaging the heating device. The method can further comprise reducing turbine resistance by reducing the power position of the turbine or opening a wastegate. The methods can further include first satisfying a start condition, and/or subsequently detecting a termination condition.