I have a 2002 7.3 with 220K on it. Its had regular oil changes with amsoil.
Over the past few years its gotten harder and harder to crank in the winter time. This year being the worse due to having to have it plugged up even at 60F outside.
If I plug the truck up for 30 minutes it'll crank, but is only running on maybe 5 cylinders until operating temperature is reached. during this process there is no smoke. If I try to drive the truck while it is cold there is zero throttle response. I can put it in neutral and floor it and it'll get to maybe 1200 Rpm and the truck will shutter.
I have pulled the valve covers and checked each glow plug and got 1.1 to 1.2 ohms on all of them. The control wires had continuity on each bank. The glow plug relay is good and closing for two minutes before dropping out of the circuit. I dont believe its a plug problem, because of the lack of smoke.
The ICP plug has oil in it. I unplugged it thinking it wasnt telling the computer to raise injector pressure and tried to crank the truck using the default pressure and it still will not crank.
I keep running myself in circles and was hoping someone could shed a little light on my problems.