Def during regen

[jacknife]

Egr Regen
Having went back and reread issue 82 page 113, paragraph 4 it states to improve fuel mileage Cummins is using DEF instead of Diesel fuel during a regen of the DPF.Unless this is a misprint as l understand it DEF is what is used during a regen not diesel. Writtwn by Joe Donnelly

 

[JLandry]

jacknife,

On the 2013/14 models, diesel is indeed used to elevate exhaust temperature in the DPF (Diesel Particulate Filter) to burn off accumulated soot during a regen cycle. Extra diesel is apparently introduced in the exhaust stream through a post-combustion injection event because there isn't a separate diesel injector located in the exhaust system.

DEF is injected into a SCR (Selective Catalyst Reduction) unit after the DPF to reduce NOx emissions.

The comment about increased fuel economy results from now being able to run the engine leaner and with more advanced timing (without increasing tailpipe emissions) due to the DEF and SCR.

On my 2014, I've happened to notice two regen cycles on my Edge Insight. They didn't last long and don't happen very often. When they did occur, I didn't really notice any impact on the fuel consumption.

Best regards,

John L.