Excessive regenerations

[Mudflap77]

(01-25-2022 )schISM Wrote:  One thing that I noticed on the screenshot you posted was your beginning DOC inlet temp. on your second to last regen attempt was at 699 degrees. At 700 degrees for more than 60 seconds the ecm will abort a passive regen, but it should have thrown a code for DOC overtemp. and you never mentioned anything of the sort. This is just a suggestion you might try, turn your regen permit switch in the dash to “off” and wait till you know you can be steady interstate driving for 50 minutes or longer. Go to data logging in INSITE and bring up the DPF monitoring parameters. Make sure the DPF status is either SCR warmup or inactive before you enable the dash switch and pay close attention to the DOC inlet, DPF inlet and DPF outlet temps after the DPF status goes to active for a passive regen. DO NOT let the DOC inlet temp go to more than about 680, the DPF inlet more than 1100 and the outlet much past 1200. That might mean gearing down and only running 55. Keep an eye on the soot load also, it should go to zero about 35 minutes into the regen. If all is well at the 45 minute mark the regen should complete and all should be good for another hundred engine hours. If it never completes or your unable to keep the temps in check it’s gonna ask for another regen in a few hours. Now if your unable to get a passive regen out of it I’d say the issue lies in the aftertreatment system itself...face plugged DOC/DPF, delta P sensor or feed tubes need to be replaced ect....If you can get a completed regen out of it try running a few days with the regen permit switch in the off position. If the system allows it for more than a few days without a DPF full error then I would start looking at the EGR system for the problem. Make sure the EGR delta P orifice ports are clean and the exhaust back pressure port in the thermostat housing is clean as well. If I had to guess what the issue is though based on the hours of the engine I’d say your EGR cooler is about plugged up with carbon resulting in higher than normal exhaust back pressure causing the ECM to command more EGR to overcome the obstruction, closing the VGT turbo to force more exhaust through the EGR valve and triggering the ECM into asking for a regen to clear the “soot” it thinks is blocking the DOC/DPF.

Pheeeeew....I apologize if I got a little long winded there but if there’s something I didn’t clarify correctly or completely please ask and I’ll do my best to keep it short. Good luck.

Thank you. I was hoping someone could see something off.
I can watch data logger all day but with no reference to what it should be doesn't do much good.
EGR cooler efficiency is always reading 98 or 100%. If that means anything.