Rawze.com: Rawze's ISX Technical Discussion and more

Cummins ISX 15 (CM 871) 2011 (engine-2009)
VGT turbocharger

I passed calibration successfully

The turbocharger position is both commanded and measured from the controller directly via the J1939 network. There is no separate "sensor" for it and therefore no separate "Voltage" for it.

"Turbocharger Position Commanded" and "Turbocharger Position Measured" is what you should be looking at.

Thank you Rawze!!! Now I know my turbocharger works well. I check it like you on your video. And I passed calibration successfully. My Commanded and measured positions shows and works well. Thanks Rowze!

Just because they pass calibration doesnt mean the actuator is good. Dont know whats goin on with the truck but mine would pass cal just fine then quit throw a code and derate pulling out the driveway. Again i dont know if ur having problems or what they are just .02 to think about.

(07-07-2017 )smorgan87 Wrote: [ -> ]Just because they pass calibration doesnt mean the actuator is good. Dont know whats goin on with the truck but mine would pass cal just fine then quit throw a code and derate pulling out the driveway. Again i dont know if ur having problems or what they are just .02 to think about.

Boost and pyro gauges are your friend. Especially when you suspect they are getting out of calibration.

I have seen a few trucks that had calibration issues. It usually starts out where the turbo will over-boost or under-boost depending on the last time it was cranked up. Shut the truck off for 2 minutes and re-start it and it acts normal again.

turbo does a span check each time the truck is started up. It then uses this span to position itself. If it is hanging up, the span suddenly becomes different. Its too bad the manufacturer was too stupid to include a raw span measurement value that can be read by the ECM/Insite so that you can troubleshoot common problems like this eh?

I have often thought of adding a small hole (tapped with threads and a plug when not used) in the side of my actuator in line with the gear so that I could insert a measuring tool for its position. that way it can be mechanically validated without having to take anything apart.

Did a turbo inspect awhile back, vg ring wasnt spanning all the way. Shop replaced it (ext. warranty) new cummins reman turbo, 150 miles of deadhead and pick up a load, bam egt go sky high, boost almost nothing limped down the road a ways boost picled up and i got it back to the shop, vg ring completely froze, replaced the turbo again (turned out some mechanical vg parts fell apart). Pull out the driveway and bam a derate and engine shut down alarm. Turn around, hook it up and its another actuator code. Replace the actuator and havent had a problem since. Well not with the turbo anyway. These vg turbos may be efficient and all but man they can sure be infuriating but i suppose thats all things mechanical.

(07-08-2017 )smorgan87 Wrote: [ -> ]Did a turbo inspect awhile back, vg ring wasnt spanning all the way. Shop replaced it (ext. warranty) new cummins reman turbo, 150 miles of deadhead and pick up a load, bam egt go sky high, boost almost nothing limped down the road a ways boost picled up and i got it back to the shop, vg ring completely froze, replaced the turbo again (turned out some mechanical vg parts fell apart). Pull out the driveway and bam a derate and engine shut down alarm. Turn around, hook it up and its another actuator code. Replace the actuator and havent had a problem since. Well not with the turbo anyway. These vg turbos may be efficient and all but man they can sure be infuriating but i suppose thats all things mechanical.

Mine went out at 580k miles. Put a factory re-man on and the truck now has 1.088 mil on it with the re-man. Replaced it myself, don't trust anyone else on that kind of stuff.