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

I recently got around to performing erg tuneup on 06 cm870 that i posted about last fall with the power issue. Truck has 510,000 miles. I removed the intake tube and it had lots of soot to be cleaned out as i have read about many times on here. I cleaned the tube good and replaced the intake pressure and temp sensors. I also replaced the differential pressure and exhaust gas pressure sensors as recommended. I also removed the erg valve and inspected it. It wasn't too bad and cleaned what i could. I checked the turbo waste gate actuator which is the diaphragm type with a rod coming out of it. I hooked a hose and air regulator to apply air to it and it moved when between about 30-40 psi as my regulator isn't super accurate. But it does move. I removed the air line that runs from the actuator to the actuator control module which is mounted on the lower left front of the engine and blew air through it. One question i have is i have noticed while servicing the truck getting ready for harvest that there is an air leak on the waste gate actuator control module around the round plug on top (about the size of a quarter) with an allen head screw in the middle. The module still has red paint on it and i am wondering how this actually works and this could also be contributing to low power and excessive smoke under load. Is this a plug and play module or does it need to be calibrated with onsite. Thank you for all the advice.

Yup, the control solenoids in the control module are leaking thru. You'll need to replace it. I strongly recommend that you buy genuine Holset replacement. Its pricey @ $800-$1000 but all the refurbished crap on the internet is very poor quality.

Also, it sounds like your actuator on the turbo may be sticking. It may need replaced also.

These will most definitely cause all your symptoms.

Thanks for the advice. I tried finding a travel spec for the actuator rod on quick serve but only found the other style specs like on an 871. I was wondering if i could check it like the smaller cummins with so much air psi there should be so many thousandths travel on the rod . Thanks

An 870 should travel 12mm with 90 psi

Anyone have any pictures of where these parts are on an 870?

This is an actuator, its located on the turbo you can't miss it.

https://images.app.goo.gl/3FiQrGdZX95ktBPA7

[attachment=5444]
Ok, I’m with you. Is there a way to test it?

Mine is just vacuum controlled, correct? CM870

Thanks

Its air controlled not vacuum. Are you having a problem that makes you suspect something is wrong with it?

Follow the air line that goes in the top of the actuator, up and over the front of the engine to the drivers side. It will lead you back to the control module on the drivers side. It should be a box either red (if Cummins original or crappy reman) or black ( if replaced with genuine Holset)