2005 F350. Just rebuilt the turbo, oil cooler, new fan clutch, egr valve. Been having some issues with the IPR acting funny but was resolved. Now, driving in traffic, stopped at a light, noticed slightly rough idle and ICP 587-607-590-602..... Continued on and about 2 minutes later, loss of power, no throttle and stall. Try to restart, nothing. Turns over fast and rough. ICP reads 13 while cranking. Unplug IPC sensor and still nothing.

Codes;
P2285
P2284
P2290
U1900

Ficm voltages are normal.

I'm thinking the IPR failed or STC.

EDIT: IPR reads 14.7 KOEO and 83.9 cranking. ICP volts .2.

 

Oil is clean and full. No leaks anywhere.

 

Loop is operational also. Registers pressure on gauge while cranking.

 

I agree, its likely the IPR I would pull and inspect the screen for damage and if you haven't updated the STC fitting you really should as allowing it to fail can be very costly as it can crack the rear engine cover and that requires removing the engine or transmission to replace the rear cover which is much more expensive than replacing the $65 STC fitting.

 

IPR appears to be working.

 

Just remember IPR value is a commanded value and not a actual movement value when checking the IPR.

 

If it were the IPR, is it possible for it to bleed away all but 13 psi when cranking?

 

yes, if it is stuck open it will not allow the system to build pressure.

 

I'd be inclined to pull/inspect IPR-could have gotten clogged with that work just being done.

if that checks out, time for an airtest.

If you are already in that deep, removing the HPOP cover to replace the STC should almost be called "Preventive maintenance"
(I had a new STC fail on me, so visually inspecting to see if its updated may or may not pan out....)

 

No luck finding a fitting to air test. I bought an STC fitting kit and an IPR. If one was to push on the plunger of the IPR, how much should it move? I get about 1/8 inch. The screen had a home in it and was dented in.

 

Sounds like something went thru IPR

 

Trash may have taken out the HPOP, has to go through the pump before it gets to the regulator.

 

I have been driving it now for about 1800 miles. I had been getting an unexplained high ICP reading (1800) at 2500 rpm with the IPR showing 14.4 under no load. Also was getting intermittent p2294. One day last week I heard a thud and all of the pressures went to normal and stayed for the last 800 miles. The truck ran completely normal until this morning, when I stopped at a light in traffic. ICP did weird stuff and the idle became rough. I drove away and about four blocks later, it stalled with 13 psi ICP.

 

It is quite common to have debris end up in the IPR after oil cooler work despite your best efforts at being clean while doing the oil cooler, lint from rags or paper towels are often the culprit.

 

I actually think the STC blew. It was so abrupt with very little warning. The slightly rough idle with wavering ICP then total release of pressure just sounds like a failing fitting to me.