I would check uvc harness, battery cables, and gpr... mine just started doing same thing.... I had an alternator and battery crap out, and my battery cables need replaced. I am going to build my own... ford wants way too much money for theirs. I noticed my glow plug relay isn't working, it cranks up slow and seems like forever.. then she fires up and runs like normal... I will say this too. any time I have a running problem I always change the oil first then retest. I was a school bus mechanic with over 260+ of these buses, from dt, t444e,7.3's.. thinned out oil will make them run like crap, die, ect.... trust me on this. just make sure your regular maintenance items are taken care of b4 you throw money at it.
best of luck
A forum community dedicated to Ford F-series owners and enthusiasts with a Power Stroke diesel engine. Come join the discussion about performance, bulletproofing, modifications, classifieds, troubleshooting, maintenance, and more!