Hi I have a 2006 F550.
7,000 mi ago I did:
OEM headgaskets & ARP studs
OEM oil cooler
sinister EGR Delete
Blue spring upgrade
motorcraft fuel filters
all injector o-rings including the rail to injector o-rings
new standpipes & dummy plugs
new motorcraft ICP & IPR
new fitting on hpop (didnt need but already had it so installed anyways)
CCV mod vented to under truck
oem air filter
I change the oil every 5,000 and use 5w40
Basically completely went through this truck while I had it apart so I wouldnt have any problems with it once I fixed the headgasket issue.
Has been starting great. Shut it off the other day and it wont start hot again. Diag it with air test and scanner. wouldnt build icp over 335. have a high pressure leak again. Pull apart and air test again. HPOP appeared to be pouring out air. Yes the IPR was closed. Replaced pump. No change in problem. Havent air tested again yet. plan to today but Im running out of things to fix in the high pressure system.
Second problem I am dealing with is a blue smoke issue. so small it can only be seen at night when there is light that the smoke can pass in front of (work lights on back of truck). But the truck stinks all the time and will make your eyes water if your around the exhaust. Narrowed the options to turbo seals, injector issue, or piston oil rings. Had turbo off yesterday. Dry as can be. No signs of any oil at all. Next guess for me would be injector issue but How do you pinpoint which injector is being a problem? Cylinder contribution test shows all cyl. are running equal even when driving it and it runs fine except sometimes when cruising in the 70-75mph range every now and then you can feel somewhat of an hesitation possibly the feeling of an injector not fully providing fuel or something would be the best way to describe how it feels. also it burns approx. 3 quarts of oil between every 5k oil change.