Good afternoon Joe! Couple other background questions I would ask is if the engine is consuming oil (ash loading DPF), was it OEM DPF or aftermarket , and when was last time air management sensors (IMAP, EBP, EGR DP) have been checked for excessive soot build up including EGR delta pressure orifices. Your DPF inlet temps do seem high so I'd agree the AFR is running richer than intended and with outlet temps mostly lower- soot seems to "larger/heavier" building more on face of DPF. Data log as you suggest and I'd add after they do some hard pulls under load I would also like some coasting events (motoring, over-run, whatever you wanna call it) and see what forward Nox sensor is reporting. See you next week. Thanks, Steve
The dpf was a cummins replacement that was put on when the new injectors were installed 30K miles ago. EGR diff pressure and egr valve opening were in a normal relationship to each other. They had replaced the exhaust gas and intake manifold pressure sensor in the process of trying to correct this issue. There was some down hill in the log but i did not post that as there was nothing I saw that was out of the normal. Fuel pressure stayed right with commanded. The engine was not using any oil. This one was a hard call for me.
This is one where you wish you could install a clear pipe after the turbo with video camera recording and see when or if it is truly producing excess PM! Hunches can get expensive. With the strategy of mobile regeneration, you start to ponder at what point do you start to erode on the turbine side of the VGT or get a slipped sector shaft. I'll tune in Saturday for sure on my coffee break to see what is next. @@ENGINESHOPJOE
