Methods and systems are provided for operating an internal combustion engine having an exhaust system and a plurality of cylinders that utilize fuel and/or oil for combustion and engine lubrication purposes. In one example, a method comprises, while the engine is operating in a low-load mode or an idle mode, successively operating distinct subsets of said cylinders at a cylinder load sufficient to increase an exhaust temperature for burning unburned fuel and/or oil deposited in the cylinders or engine exhaust system. Herein, each successively operated subset comprises at least one but fewer than all of the plurality of cylinders, and the cylinders that are not currently being operated in a subset are operated in a low- or no-fuel mode.