Join Date: Dec 2008
Location: Spokane WA. area
Thanked 984 Times in 750 Posts
Icp should hit 4000psi instantly when pounding the go pedal. Possible ipr or icp issues, or high pressure oil leaks, wire chaffing or bad harness connections. Also, if the turbo unison ring was frozen, then turbo housing could be worn too like mine was. I cleaned mine only to have it malfunction again a few days later. I'm sure you checked the obvious, like the exhaust for restrictions and the air filter too. If it still has a cat-conv thats a possibility. What is your icp at idle? Another thing is the maf sensor. If it's an early 04' it may have the inferred ebp sensor flash O6E17. Which then uses the maf sensor for boost and fuel calculations. I had the connector on my maf sensor go bad, wasn't getting the correct signals through from the maf, ford makes a harness mod kit for the maf that comes with a new connector and harness to extend the old one at the maf sensor. Early 04' models still have the icp sensor under the back of the turbo on the hpop housing. Late 04' the icp sensor will be on the passenger side valve cover. If its still using the ebp signal, like a later model would be, then maybe try cleaning out the ebp sensor and plumbing. If your oil pressure is being bleed off either through the ipr valve itself or from hpo leaks, then you will never get enough fuel delivery and exhaust gasses to operate the turbo. Tough to diag something like this without being there, but hopefully it's a simple fix, if there is such a thing. Good luck and keep us posted, never can learn enough about these motors.
Jan 03' built 6.0/F250cc4wd trqsft/SCT-tuned by KEM-Performance/Garrett Powermax vg-turbo/blue spring mod/gauges=egt+boost+fuel+SG2/exhaust/airaid intake/DR 4.5 lift/dual bilsteins/315's/greasable ball joints/powerstop/smittybuilt/kc lights/high idle mod/roll-n-lock/Mobil Delvac1 ESP 5W40 with (Archoil AR9100 in the oil) and (AR6200 in the fuel)