I know this topic has been discussed before but instead of sifting though all of the online forums trying to find a situation similar to the one I have I am just going to post a new thread with my info and see if I can get some help here.

2007 F250 6.0, Studded, Deleted, Injectors replaced ~8,000 miles ago, Blue spring, Probably a few there things I can't think of off the top of my head.

Recently I started noticing that I was having to crank the truck longer than normal to start it. Thaited is has never been an issue before. When I swapped out the injectors I replaced the standpipes and plugs with Ford parts. I tested my ICP before doing any work and it was running really low before cranking. I assumed the normal issues, possible standpipe O-ring or nipple O rings on the oil rails. So I went ahead and replaced all of this stuff. Checked what was already in there and didn't find much to be concerned about. I also inspected the injector O-rings but they all looked to be in good shape. Got it back together today got it fired up and running. Shut it off, waited a minute, fired it up. Still a little longer than I remember but not terrible. Shut down and waited an hour or so. Went to fire it up and had to crank forever again. I put my computer on it to check some things and this is what I got.

While running Idle:
ICP steady around 595psi.
Desired Pressure 593
IPR 21.5% ( stays around 20-23% no matter throttle position.

Shut it off and watched.
ICP almost immediately below 200psi and within a few seconds drops to about 90psi then holds there a drops very slowly until it hits zero after about 10 minutes or so.

Starting back up
ICP Sits a zero or near it for a few seconds then slowly starts to build pressure until about 15 seconds or so of cranking fires it up.
IPR was at 84% during cranking.

I did run a KOER test using AutoEnginuity and it came back with a P2290 pressure too low code. This doesn't show up anywhere except when it run the test. I don't know what my pressures should be normally but it seems around 600psi should be OK from most things I have read. Except during cranking it seems to stay about 590 or more. I am not sure what to look at next and hope that one of you guys can point me in the right direction. If you need more info just ask and I will get you what I can.

 

Did you pressurized the HPO system with shop air through the IPR port?

 

How do I do that exactly? This is about the only thing on the truck I have not messes with so it’s all a little new to me.

 

You need a tool like this.

https://www.ebay.de/itm/273520744423...hoCkEcQAvD_BwE

 

I have a tool to pressurize through the ICP port... I don't know if that is helpful. I did do that just a few minutes ago. I can hear air leaking somewhere. If that is similar to what you are referring to, how can I tell where it is leaking. I assume I will have to pull my valve covers..... again. This thing wears me out. HA!

 

Don´t do it through the ICP port, do it through the IPR port. Pull valve covers. I let it pressurized for several hours if there seem to be no leak . It can take a while till you can hear it.

 

I don't see where you replaced the STC fitting off the HPOP? Did you just not write that down...?

 

Sorry I have been out of town for a few days. I am now back working on the truck. I went through a procedure I found online to test of leaks. This would be using the ICP port and it seems that most people use this when testing. So I connect air, I can hear the air going somewhere. I cycle the IPR on with my scan tool and then I hear nothing. I have checked around using a stethoscope and I do not detect anything anywhere. My next test I am planning to do while waiting for some advice is to put a valve on my air line and a pressure gauge and watch to see if the pressure holds and for how long. At least long enough to see if it stays or starts to drop. I don't want to damage something on the IPR by leaving it powered on for too long. At any rate, when I was testing on my scan tool the other day, it would take a long time to build pressure but it would eventually get enough to start. between 10 and 20 seconds of cranking. It runs fine. Pressure runs in the area I have been told is normal. As soon as you turn the engine off the scan tool shows the pressure drop down to around 100psi almost immediately. I have been told this is not normal. But I am not 100% sure what I am supposed to be looking for. Thanks!

 

Dan, I did not. I last worked on the truck I think three years ago. I have had no issues since then. But this was not something I was aware was a potential problem when I had it torn down. I knew issues with the HPOP could happen, but since I had never had a problem in that area I didn't look into it. I assume that could be an issue now but I am not sure how to diagnose that other than to actually remove it. I am trying not to take the whole thing apart until I know for sure the only think left is to pull it out.

 

I have a truck with almost the exact same issue. Long crank (10 seconds) until pressure builds (verified on scantool) and it fires up and runs good.
I assume its a standpipe issue, I will be pulling the valve covers and attempting a leakdown check in the next couple days.

 

I recently replaced my standpipes, and I don't even think they were the issue. My injectors are pretty new so I also doubt those lso replaced my nipple cup seals while replacing the standpipe seals recently just to make sure everything was covered. I do not currently detect any leaks under the valve covers. I have even removed them just to make sure I can check everything close. I have a feeling it may be the STC fitting I have been reading about but I hate to tear in that deep until I have a better feeling that is what it is.

 

You running a tall (aftermarket) oil filter cap?

 

I have the OEM Cap and Filter.

 

Many of the '05 - '07 owners replace the STC fitting proactively - while it can have a slow leak it also is known to fail quite suddenly and with force that can crack/break the aluminum cover adjacent to it. So then you are both dead where it fails but in addition have to replace a cover that is difficult to get to w/o an engine or trans pull. While your current problem may be something else, I'd still recommend planning on doing the STC replacement sooner than later...

Best of luck - you have all the right eyes on your thread...

 

P2290 is a running code, so it isn't just startup/cranking.

Totally agree with the above that the STC fitting can leak a little or a lot, although typically it tends to be a larger leak.

Also could be the "pesky" standpipes. Seems like a lot of times the o-rings get torn up on installation.