Power surge on CM870???

[Rawze]

(05-03-2020 )4lanefarmall Wrote:  ... as not to fall below 1000 rpm
...

The ISX should be driven in the 1500 - 1900+ rpm range if your more than half way on the fuel pedal. - It is not good for them to lug them below 1450 or so while pushing the fuel pedal far down or going up hills on the cruise control.

If you have a de-mandate program in it, or suspect it is programming related, or that the ecm is holding it back due to some various sensor or reason ... Test drive it while monitoring engine mode selection logic among other settings. -- the 'Fuel_Control_State' setting will tell a person what is in control of the fuelling (I.E.>Power) at any given moment. Someone may need to also do some testing with it and make sure it is not jumping/changing engine modes and causing unstable power output, etc. - Could be the engine is changing modes due to bad/incorrect programming?. Could be many things.