Cummins isb 6.7 b101 cm2350 dozing pump issues

[joed2323]

(02-02-2021 )Rawze Wrote:  

(02-02-2021 )joed2323 Wrote:  Rawze, unless I'm not following you, DT90420 is this the same ecm calibration as DT90426.06?

I saw the mistake when you posted the other photos and went back and checked the DT90426 program too. Everything I said above still stands, as there are very little differences in the 420 vs. the 426... therefore I left my post above alone.

I can only assume you have the wrong program in your engine and that at some point, some moron tried to up the HP in it by jumping CPL's ... this is what all data points to so far that has been provided on the forum here.

if I owned it, I would start by putting the 100% matching and correct program (latest revision) back into the truck and go from there. That is rule#1 when someone comes on here and says they have emissions system issues and can't figure out how to solve them. - Wrong program or Wrong power level settings for the exhaust system you have on the truck = noting but issues after a while. Seen this so many times it is not funny and a after a while someone has nothing but problems due to some jack-leg trying to get more out of their engine and doing this. I have even seen OEM st$ealersh%its do this to people's engines. OEM shops are typically just as clueless as anyone eles out there who would do such a thing.

Ok, so I was able to get truck over to a cummins dealer for the ecm calibration update. They agreed the wrong cal was installed on truck. They checked over the dosing module/def sending unit/def dosing injector and found nothing wrong with any of it.

The cummins tech said that the issue if it comes back has to be with fords wiring or wire they run from the dosing module up to the ecm.

He also said that he isn't sure which wire it is and would have to ohm out the wires to find fords wiring since Ford doesn't offer schematics.

So drove truck about 20mins and imagine that the same issue came back with losing def pressure just like previously.

One thing I noticed is that the def fluid dosing valve commanded position never changes from closed.
I did happen to catch it as i was driving and monitoring insite, it changed from closed to open like for a split second but it was fast and it never stayed open only closed
It never goes to open even when the def dosing unit state says its dosing, this can't be correct?

The cummins tech did say it is possible that the dosing module that was recently changed is faulty. But the dosing module did pass the def module override test and he said it injected enough def into the beaker and flow tested fine.

When it builds to 130psi, it holds pressure and voltage for a bit, but when it looses it, it is a slow drop of pressure and volts down to about 0.6 psi/0.8v

Its a repeated cycle over and over while driving, def pressure builds to about 130-143psi and then slowly drops back off to 0.6psi, it stays at 0.6 psi for a bit then climbs back up to 130psi and stays their for a bit and then drops slowly back off again.

The only code it is currently throwing is:
3574

Now I'm back to square one again, fml