2013 MaxxForce International engine code: spn 3251 fmi 2

DPF differential pressure too low. This is usually a broken pressure sensing tube at the DPF or DPF diff pressure sensor.

 

It is the metal tubes on the DPF filter in your exhaust. The DPF looks like a muffler. There are two of the tubes. They screw into bungs on each end of the DPF and go somewhere, usually in the middle, to the sensor. At the end of the metal tubes are flex hose sections that can tear or split, then those connect to the sensor. The sensor is just plastic, so the ports on the sensor can easily break too.

 

[QUOTE="Heavyd,
Hi there
I have a 2010 prostar with Cummins isx. It shows warning engine light on highway with code 3251 fmi 15. When get off the highway warning engine light replace with regen light. Do a park regen, every thing become fine. No code shown. Same thing happening every day. I had bake filter, put new doc & new turbo. Still same problem. Plz suggest me how to come out. Every time Machenic throw new parts.

 

Was the aftertreatment injector ever serviced?

 

Yes. That is also serviced twice