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+--- Thread: Cummins isx cm871 fault 2637 (/showthread.php?tid=8522)
Pages: 1 2
RE: Cummins isx cm871 fault 2637 - Mr Hagg - 10-31-2022
A few things one looks like you maybe using oil looks soot plugged from oil to me... Then as far as heat to start regen could be a few things. Dosed may not be dosing fuel, doc maybe bad and will not ignite fuel or turbo is no good and will not cause enough back pressure to create heat. Could also be Doser injector tip is sooted over.
RE: Cummins isx cm871 fault 2637 - snailexpress - 11-01-2022
My 871 did the same soot. It was cracked valve on one cylinder.
RE: Cummins isx cm871 fault 2637 - Mrt800 - 11-01-2022
(10-31-2022 )Rawze Wrote:Same time I replaced the dpf I got the doc cleaned out ,also new dozer ,sensor , temp etc.(10-30-2022 )Mrt800 Wrote: That’s the doc I got cleaned out in April.
How was it done?... By an OEM with the proper Cummins certified machinery?.. and if so.. was the flow rate tested to be good after? .. or was it cleaned out by some other nefarious means?.
Was the DPF done at the same time?...
... and did anyone bother to do a proper Reset Procedure in Insite when it was re-installed?
did anyone bother to do a thorough egr Tune-up on the engine itself?
Has anyone bothered to see if the Doser injector is seeping/leaking fuel at idle?.
I replaced the egr and did the tune up . I noticed that the imap sensor was carbon
Packed completely.
RE: Cummins isx cm871 fault 2637 - Mrt800 - 11-01-2022
(10-31-2022 )Mr Hagg Wrote: A few things one looks like you maybe using oil looks soot plugged from oil to me... Then as far as heat to start regen could be a few things. Dosed may not be dosing fuel, doc maybe bad and will not ignite fuel or turbo is no good and will not cause enough back pressure to create heat. Could also be Doser injector tip is sooted over.
It’s a new doser, Yes it’s using some oil I’m going to pull the exhaust manifold like
someone mentioned on the thread. Or maybe just replace the valve seals . I’ve had the valve
tool for three years ,I think it’s time to use it. I guess it won’t hurt.
RE: Cummins isx cm871 fault 2637 - Mrt800 - 11-01-2022
(10-30-2022 )Rawze Wrote: Engine issues cause DPF issues.. have you done a thourough EGR tune-up on it yet?
ref: https://youtu.be/FhJxpyS5MpY
================
WOW!>.. that DPf looks done for... how old is it?.
It is time to remove it and the DOC and take them to heve them baked out, de-ashed, and flow tested. Can be done by an OEM steslers$it for a few hundred bucks.
Also that looks like oil intrusion.. someone needs to pull the exhaust manifold away from the head and check to see if valve guide seals are getting wet on a cold start.
Well check exhaust while manifold is removed for valve guide leaks
RE: Cummins isx cm871 fault 2637 - JimT - 11-01-2022
(11-01-2022 )Mrt800 Wrote: Same time I replaced the dpf I got the doc cleaned out ,also new dozer ,sensor , temp etc.
I replaced the egr and did the tune up . I noticed that the imap sensor was carbon
Packed completely.
Not sure why the DPF was replaced, but the DOC also wears down over time. Often when the DPF reaches the age of replacement the DOC is usually due as well. The precious metal coating wears down and doesn't react as well, or at all. Doesn't take much non-ignited fuel to coat the DOC and then attract soot build up and clogging. Also, leaking fluids, especially coolant, can wear away at the DOC's reactive coating causing reduced performance and shorter life span. Simply put, it's often the case that the DOC should be replaced along with the DPF.
This isn't to imply that you don't have some other issue or issues, but as the DOC conversion efficiency degrades over time you will get longer and more frequent regens, less efficient soot burn off and more clogging as soot builds up. Probably not even noticeable until it either gets really bad or something else further impacts the system.