Is the regen where the engine speeds up to clean the exhaust out? I know the Fords had the schit, didn't know they all did now. Sweet Jesus, phouc that.
Regen is where raw diesel is injected into the DPF to burn off the soot. From what I have read, early versions injected diesel into the exhaust stroke, but that caused trouble with cylinder wall washing. The newer Duramax has a 9th injector to inject diesel directly into the filter (don't know but I think the others are the same now). The idle is sped up at a stop to assist in keeping the DPF temps high. You won't notice a regen on the open road. You can notice one in town due to the higher idle. The big pisser is it uses more fuel and hurt mileage. It is a pisser but it's the EPA price you have to pay to get 400hp/800 torque from the factory.
