Power surge on CM870???

[4lanefarmall]

(05-03-2020 )4lanefarmall Wrote:  cowboy, I'm interested in what you found! I'm having exactly the same issue. and guys its not that he's driving it like a rocket, (at least on mine) when going thru the gears its really sluggish and then out of the blue without changing pedal position it will throw u back in the seat instantly and reach shift point ( as if you were in a rocket) and I noticed lately that it is running higher boost on flat roads like 20 to 25. It still achieves full boost (about 37) but takes longer to get there

also I should say don't believe it to be turbo lag, cause at times when really acting up i have no pedal at all until around 1000 or 1100 rpm so I have to stay on high side of rpm while shifting so as not to fall below 1000 rpm. Also don't know if different issue but cruise control keeps kicking off now and engine brake when using them. I really need some help please been into international 3 times now, they blew out air line to turbo, and replaced 2 injector actuators. its still the same.

[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.

[4lanefarmall]

Thanks for quick response Rawze. trying to narrow the search,your right could be a lot of things. And boss says he not throwing no more money blindly at it. But its driving me nuts to drive(knowing its not right) and really lacking power. So cowboy is having exactly same issue if he figured it out, I could tell the boss what he found.

[tree98]

Why don't you check the vgt ring movement with your hand for proper range and ease of movement like Marek said? Wouldn't take very long to do. Or pressure test your cac/ pressurize the entire engine?You're gonna have to turn some wrenches and try some things.

[4lanefarmall]

Yah, absolutely thats going to be part of the process. I believed from beginning it was an injector cause to me it seems like running on 5 cylinders then all the sudden 6, so leak down test, (international says these injectors don't go bad) actuator check, (they used volt meter) then have them pressure test the system. Thanks again.

[Nilao]

All injectors go bad. It's a mechanical device with moving parts and seals. It's inevitable.

[4lanefarmall]

Ok finally fixed! Incase anyone interested or is dealing with same problem. My boss brought the truck directly to CUMMINS for any warranty issues, and they performed leak down test (they said bubble test) and found 2 faulty injectors! And also replaced 1 fueling actuator.
Thanks For All The Help
EVERYONE

[Rawze]

(05-16-2020 )4lanefarmall Wrote:  Ok finally fixed! Incase anyone interested or is dealing with same problem. My boss brought the truck directly to CUMMINS for any warranty issues, and they performed leak down test (they said bubble test) and found 2 faulty injectors! And also replaced 1 fueling actuator.
Thanks For All The Help
EVERYONE

i am surprised they did an injector leak test. Most OEM facilities any more are dumb as rocks any more and when you tell you want a leak test done, they have to go look it up cuz they never heard of it.lol

[4lanefarmall]

Yah, I didn't suggest anything, the leak down test was the first they did. (Surprisingly)