Change the ICP on 2004 f250 6.0 deisel

Yes, I would say it is the head gasket again. Have the head checked for flat surface once removed to replace the gasket.

A turbocharger can leak. Some of the gaskets might be shot and need to be replaced or a hose might need to be replaced. If the turbocharger itself is leaking and not a gasket then the turbo housing is probably cracked. If you get the turbocharger replaced it should last a good 20 years or so. The only thing that usually wears out on turbochargers are gaskets and thrust bearings.

If the vehicle doesnt start you will need to know what the ICP shows(this has a high failure rate) Disconnect the ICP this will default the PCM to failure mode management,this is a alternate strategy the location of this sensor front of the engine threaded in the left cylinder head by the way dont use either use WD40 or any similar lubricant.Make sure the fuel pump is working its under the vehicle right below the driver seat area have someone crank it and feel for it coming on

Check immediately the turbocharger! DO NOT START THE ENGINE WITH THIS KIND OF PROBLEM!
Remove the air inlet axial center hose of the turbocharger, in other words the compressor air inlet hose. Then check axial & radial gaps of the turbocharger rotor.
Check also the turbocharger oil pressure supply. Check the engine oil level also.
Repair & replace bad pieces.
In the most cases the turbocharger is out of order when engine puffing off blue smoke and losing power.
If the car goes in "limp mode"!!!
After scan the EDC-15P engine control unit with a VAG or KTS -BOSCH diagnosis tool you will find this: Fault code: P1557-Turbo Boost pressure control exceeded
1. Engine stopped and ignition switch off. Check all pneumatic connections and hoses between turbocharger actuator = pressure unit for boost-pressure control, boost-pressure control solenoid valve, vacuum reservoir, EGR control solenoid valve, intake-manifold flap solenoid valve, EGR valve with throttle - part of intake manifold. Also the vacuum connection between tandem pump and brake booster. If you find something wrong replace parts. If not go to step 2.
2. Extract the hose of the turbocharger actuator = pressure unit for boost-pressure control part of turbocharger. Instead of the original hose you must place another 1 meter long hose with the same inside diameter, and then you check to inspire yourself the air from the other one extremity of this hose. The mechanical connecting rod of the turbocharger actuator must have a smooth and whole motion. If you can do that with your mouth, then you must replace the boost-pressure control solenoid valve. If you can not reach this with your mouth, then you go to step 3.
3. This is the most difficult work. The problem is that the soot particles deposits inside the turbocharger plugging the variable nozzle geometry mechanism = adjustable vanes of the turbine. If the turbocharger actuator is not able to adjust the turbine vanes the charge air pressure increase too much and ECU (engine control unit) go in "limp mode" = engine protection software. As a result the "limp mode" engine still running until you turn the engine off (ignition switch off) and back on when the "limp mode" is deactivated, but the fault still remain in ECU memory!
4. You must be able to extract the turbo from the engine and then to disassemble the turbocharger, clean inside adjustable vanes mechanism and refit all.

need to monitor ipr pressure (injection oil pressure)must reach 500psi
in order to start engine
may have failled o -ring or stc fitting in injection side or possible ipr failure
valve cover right side front icp sensor removed apply 5000psi gage and
crank engine over have someone monitor and report
if this pressure is less then 500 psi it will not start removed gaged
key ignition at run apply shop air min 100 psi and listen at oil fill for gurguling oil sound
if so oil leak in hi pressure oil side

1 - Remove the turbocharger intake tube
2 - Disconnect the charge air cooler inlet pipe
3 - Remove the push pins on turbo cowl
4 - Disconnect the turbo VGT solenoid
5 - Remove the oil supply tube
6 - Using the special tool, remove the oil feed tube
7 - Remove clamp from the turbo down pipe
8 - Remove the clamp from the turbo inlet
9 - Loosen the exhaust inlet pipe-to-EGR cooler clamp
10 - Loosen the RH & LH exhaust inlet pipe-to-exhaust manifold nuts
11 - Remove the rear turbocharger mounting bolt
12 - Remove the front mounting bolts
13 - Position the turbocharger and remove the turbocharger drain tube
14 - Remove the turbocharger

If you cant do it with these instructions put down your wrench and take to a dealership for a professional to work on it

Yes it will fit

remove trans oil pan. there you will also see your trans filter,

remove the rh valve cover, unscrew the sensor, replace the valve cover.

Remove panel in trunk (round one on each side) reach inside unscrew toggle bolt then remove the entire taillight assembly, may have to push from inside. When you have the taillight assembly out you will see where the bulb is on the back of the assembly, remove and replace with new bulb. Put taillight assembly back in, replace toggle bolt make sure it is tight and replace panel. It is a pain the first time but I have done this 3 or 4 times it gets easier.