abstract |
Methods and systems are provided for fuel post injection for diesel particulate filter (DPF) regeneration. In one example, a method may include, responsive to a request for generating exotherms in an exhaust system of an engine while combustion is discontinued in at least one cylinder of the engine, injecting fuel into a cylinder within a threshold crank angle range around top dead center (TDC) of a compression stroke of the cylinder and also within the threshold crank angle range around top dead center of an exhaust stroke of the cylinder, the threshold crank angle range extending from no more than 40 crank angle degrees before TDC to no more than 40 crank angle degrees after TDC. In this way, fuel post injections may be injected +/−40 crank angle degrees after TDC of the compression and exhaust strokes to increase exhaust temperature while avoiding wall wetting and oil-in-fuel dilution. |