Regeneration

Have they checked the doser injector. making sure that it is spraying the fuel into the aftertreatment. It has to spray into the aftertreatment in order for it to heat to a certain temperature to blow out the soot. With a new dpf you should not have to regen alot unless you are idling alot or running in stop and go city driving. Also could be just a sensor that needs to be cleaned or replaced. What year is the truck?

 

Have to change dpf filter rhey usually go bad about 300,000miles

 

After u do a 20 min parked regen do you lose power after a while if driving

 

http://www.thetruckersreport.com/tr...-isx-cm871-technical-discussion-new-post.html
This is a forums on this site very informative!. The motor might be different but talks all about dpf and egr tune ups it is well worth the read. Help me to understand the whole egr system. You might have to browse through the pages but look and let me know what you think. If you cant open it go up to the seach bar and put in cm871 technical discussion that should pull it up.

 

Have them check fuel pressure at priming port. Those engine are really bad about having a stuck open overflow valve, causing low fuel pressure