I just got my 04, 6.0 Superduty back from the shop after having the HPOP replaced and I noticed when I turned the key to start the truck that the cycle time for the glow plugs was much shorter than before. (about one second) This concerned me but the truck started ok and ran great so I took the truck home. The shop was closed so there was nothing I could do anyway. I drove the truck that weekend and it continued to do the same thing but still stated fine. After that the truck sat for about four days and then started hard. It turned over for about 9 seconds before it fired. I’m taking it back to the shop tomorrow to see if there is anything that the mechanic could have done to cause this problem. My question is! Does anyone know if there is anything that you know of, that the mechanic could have done to make the glow plug do this? They were working fine before I took it in.