Brand new to us 2005 6.0. It ran fine for the first week we had it and then it started the no start when hot. This morning it would not start after sitting overnight. KOEO and cranking/idling ForScan data and graphs are below from this afternoon. Of course, it started up so I could not get the graph of the issue in real time. But when it would not start earlier I watched ForScan data and the IPR was at 84.77% duty cycle and the ICP was between 480-508 and it would not start. I'm assuming it's something with the high pressure oil system but am kind of lost on what I'm looking at or for. I've read about the air pressure test so I will probably order an adapter tonight to try that. Does any of this data narrow down the failing part of the HPO system?

- oil level on dipstick is right at the MAX marker and does not smell like diesel
- I have not done the fuel checks yet; i'll work on these when I have a helper
-ForScan data for KOEO
-ICP V: 0.24 - 0.25
-FICM M power: 47.5 - 48.0
-FICM L power: 11.0 - 11.5
-FICM V power: 11.0 - 11.5
-IPR duty cycle: 14.84%
-fuel tank level: 72%




ForScan data cranking/starting
-Cam/crank sync - if this is the CPM / CKP sync then YES
-FICM Sync: YES
-FICM M power: 47.5 - 48.0
-FICM L power: 10.5 - 11.0
-FICM V power: 10.5 - 11.0
-RPM: 212 - 230 while cranking, ~700 once running
-ICP V: <1 while cranking, ~3.4 once running
-ICP PSI: builds from ~100 to ~530 while cranking, then about 3500 when idling
-IPR cycle: builds from 14 to 84.77 while cranking, then 59.77 when idling
-vREF: 5.00 the entire time




Thanks in advance,
-Chris

 

I forgot to mention that the PO said he did the standpipes and dummy plugs and he left us the originals that he removed.

And the trucks oil pressure gauge does not move until it started up and was running, similar to my 2003 7.3PSD.

Thanks,
-Chris

 

When you have the no-start-situation: can you upload a video cranking with removed oil filter to see how long it takes to fill the oil filter housing ?
push down the drain valve with a screw driver.

Thats what you should see:




This is the first step because you mentioned a not moving oil pressure needle when cranking.

 

Thanks for the video and guidance. I won't be able to get back to the truck until Friday at the earliest; I'll post an update once I have new information.

 

Issues on one of the 7.3's this weekend, so we only had time to do the low pressure test with the drain open and it filled in ~10 seconds. Our next free time will be the test with the drain closed and hopefully i'll have a tool to hold it closed to make sure it's not leaking down. More to come....

 

Baseball has taken over our lives for now, so we had a little bit of time to work on the 6.0 today. We completed the air pressure test through the ICP. 115PSI and we could hear a relatively quiet air leak from this location. The stethoscope is at the back of the valley, picture from the passenger side valve cover. I believe this is telling me I'm going into the HPOP, possibly for an STC fix. My question is - could it be an incorrect diagnosis because we didn't use the IPR port for the air pressure test, and I couldn't find in FORScan how to control the IPR to close.




Thanks,
-Chris

 

You MUST close the IPR when you are air testing from the ICP port. The IPR is essentially a "dump" valve, and normally open unless commanded closed.

If you do not have a scan tool that will command the IPR closed, then get a spare IPR connector and directly apply 12 volts and ground while testing (but not for long periods of time).

I have my doubts on it being your HPOP, and for sure you can't tell until you do the testing correctly (close the IPR).

Get this tool (or better yet, make your own for less money):

https://www.jbtools.com/otc-6764-for...pr-controller/

 

Thank you for the clear information, Mark. I ordered a pigtail connector for the IPR and we wired it so that pin 1 went to battery + and pin 2 went to battery ground. I did NOT hear a click when we connected the ground like I expected to hear. We turned the air on at 115PSI and could hear air easily. The stethoscope isolates it best to the top of the valley, in front of the HPOP. Power was only applied to the IPR manually for about 30 seconds to hopefully avoid damaging it.

So now I'm wondering if not being able to hear a click points me to the IPR? It is now currently struggling to start even when it has not been started in 24 hours - takes about 20 seconds of cranking before it builds enough oil pressure to finally fire up.

Picture of where the stethoscope sounded the loudest, as seen from the passenger valve cover.



Thanks,
-Chris

 

The IPR valve does not click when activated/ deactivated .

This is how I test them



Not a friend of testing via ICP sensor port. I always test at IPRvalve port.

 

Thanks Hartwig, is that a custom homemeade test box you plug the IPR into to test it in isolation?

I assume to avoid making or buying another test tool piece, I gain access to the IPR to remove it, then plug an air test adapter into the IPR port and if no air is heard, then I can assume the IPR valve is the issue and replace?

Thanks,
-Chris

 

The orange part is a 3D-printed housing with the dimensions of the IPR valve port in the pump. In conjunction with the IPR controller, you can use it to test whether the valve is responding.

 

I tested the IPR valve with a similar setup and I can hear it trying to close but it doesn't stop the airflow. Replacement IPR valve passes the air test. We'll put it all back together tonight or tomorrow and cross our fingers that it's the only failed part of the HPOP system.

Thanks for your help on this - I sure wish the IPR was just a little easier to get to without taking anything else off!

 

Your description with the stethoscope location accompanied by air escaping sounds suggests the IPR may have had junk in it or bad spot coil not fully able to function maybe aftermarket part

how was the IPR screen

Sounds like things are headed right direction

 

This is after it has been on the shop floor for a few days so I can't say what it looked like when it came out but there is definitely debris on the screen. I can't get the screen off of this IPR for some reason....

After putting it back together this morning, we monitored the ICP and IPR duty cycle. it cranked for about 20 seconds building pressure (makes sense because the system had been open) and then started right up. We let it idle until the oil temp hit 150F and then turned it off to try a hot start. It just cranks and cranks and does not build pressure higher than about 220 PSI, no start.

We're going to let it cool down a bit and then hook up the air pressure test pigtail and redo that. I'll follow up when I have more information.




Thanks,
-Chris

 

I was expecting the old IPR screen to be worse maybe a hole thru it

does it have correct oil filter cap
and filter