CM871 poor power and fuel econ

[Grounded Pilot]

(07-11-2022 )Grounded Pilot Wrote:  Good afternoon ladies and gents!! I have finally gotten more things straighten out on this truck. All 6 injectors are now replaced and my fuel mileage has come up to running in the high 5’s most of the time. It is still sluggish on throttle and the turbo seems to lag behind. When I run the engine status monitor it says “defueling due to insufficient oxygen(boost pressure)”. I know it says it will do that under hard acceleration but it will do it about any time you increase the throttle % unless you are deliberately very slow on the movement. It has new filters and a new turbo and actuator. Also a new airflow sensor and exhaust gas pressure sensor. The OEM ambient temp sensor reads 72° all the time but the intake temp seems to read correctly. Also, my fuel flow jumps around a lot. At idle it will jump from .8gph to 2gph and it will jump 5+gph while pulling. Any ideas or is that another bad sensor?

I finally got ahold of a Cummins inline6 adapter kit. I’m still learning how to run the insite program and I need guidance on how to pull the programming to send it to Rawze for review? And where to send it Mr Rawze?

Thanks all!! I really appreciate your help and knowledge!

Another question that pertains to the above post. What sensors are used to give the ecm its torque and HP readings? If I get this thing up in the 1600-1750rpm range sometimes it will all the sudden start pulling like somebody stepped on its tail! And it will surge if the rpm starts picking up to quick, especially in 3/4 holes low range and 1/2 holes high range. (13 speed). Have not caught it yet when I have the system logging, so not sure if its getting the "defueling due to oxygen" engine status. BUT, I see on my Scanguage D display when it does this that the fuel flow reading seems to stabilize some and begin climbing consistently rather than bouncing around?? Is that and indication that the fuel flow/pressure sensor is faulty?? No codes, but my exhaust gas pressure sensor was broke off and I didn't get a code (also didn't have insite then either, just the scanguage and what the mechanic said). I've had to replace a bunch of sensors due to corrosion and malfunction, so just checking if there are more that I may need to check/change to make sure the ecm is getting the proper data.