Ok, this is what I've got. '07 6.0 that when starting it wants to turn over but it only makes a strange vibration like it is going to start but then just stalls (my wife describes it as purring and then it just dies off). The tach moves but when I press on the fuel peddle there is no response. This goes on anywhere from 5 minutes to half hour of trying then it starts and runs great. It is at the dealer now and it is starting fine! They cannot find any codes in the system. They think it might be the FICM, wouldn't that show a code?
Any ideas would be great.