FLD120 12.7 LOW POWER

This. A small leak results in huge loss of power. Pressurize the cac to 40 lbs. If it loses more than 3 lbs in a minute replace it.

The symptoms you discribe sound exactly like a bad turbo. But any leaks between turbo and intake have those same symptoms.

Also, is your turbo wastegated? If so check the vacuum hose and rod off the wastegate actuator. I replaced that c clip on mine Hadid a dozen times.

 

Ok, how long have you had the truck. And wheen did it develop the problem? And most importantly what was done to it before this issue developed

 

White smoke and shuddering or studering has nothing to do with turbo or charge air cooler

It's fuel related or electrical.

Check fuel pressure first.
How old is the pump???

 

Yeah cuz the pyrometer is going to give you those symptoms . Better check that.

 

check to see if anyone has replaced any fuel lines recently or maybe supply line is plugged had this issue on a star someone replaced the fuel line and did not properly put in the fitting so it was only getting part of the fuel and it started smoking on higher rpms