OK here's my story. 03 6.0L w/ ~150K miles no real issues up until about 4 months ago. I started feeling a shudder once i was up to ~70 mph and backed out of the throttle slightly. If I got back on the accelerator enough to kick into passing gear the shudder goes away.
So I took it to a couple places and they dont have any real answers but recommend a new EGR Valve and ICP Sensor. I replace still have problem.
I try another place and they say the alternator voltage is low maybe not getting enough voltage to the computer so i change the alternator. Still have problem.
One day on the way home i hear some horrible noise in the tranny so i take it to a tranny shop. They inspect and the O/D is out of spec so i have a soft parts tranny rebuild kit put in. I am towing a 5th wheel so I have my torque converter replaced at the same time. Still have shudder problem.
So now i just feel like im never gonna get it fixed. I am heading up to Globe this weekend towing the trailer up a pretty steep grade and decide since i have this new tranny to step into it and see how it handles it. A few miles into the climb, POW. I loose power but engine still running, i look in mirror for fluid on the road but there is none. I find a pull out to get the trailer off the road and shut her down. I crawl underneath and tranny looks OK. I pop the hood and all looks OK. Decide to head back down off the hill. Engine wont start. Upon further inspection I end up finding the intercooler hose blown off. 5 minutes, put it back on engine starts and all is well.
Long winded story to get to my real questions.
1) If intercooler hose is blown off is there a sensor that keeps engine from starting?
2) Shudder problem is now gone.
Could that coupling have just been leaking and causing the shudder and not blown off until i got a good sustained load on the turbo?