My first 6.0 problem started yesterday, at 136k miles. It did this once last summer, but started right back up, and hoped it was a fluke. It happened twice yesterday. No dash lights, no smoke, but I think the problem has been coming. I've noticed lately, turbo spool-up has been lazy. Step down from a dead stop and it takes a while for the turbo to spin up. But, when it does, you almost have to back-off because she takes off.
I've looked into what it's going to take to tackle the STC fitting, as well as o-rings on the plugs. Looking for advice on where to start, and make sure that is the problem. Any help would be greatly appreciated!
2005 Excursion - completely stock
Engine built 11/2004
136k miles and maintained well
Oil: 2k miles on Lubrication Engineers 15w-40 w/ Motorcraft Filter
Fuel Filter: 2k miles on Motorcraft Filters
Diesel-Kleen used at every fill-up
Conditions at Problem
Sat for 6 days w/o running - 96 degrees outside (typical Florida heat and humidity)
Drove 6 miles, shut-off, restart no problem
Drove 3 miles, shut-off, restart no problem
Drove 12 miles, shut-off, no restart 5 mins later
Let it sit for 20 mins and it restarted