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Matt, once again the numbers you are reporting are inferred values from the PCM at the ~ 20 second cranking mark. After a period of time the PCM will ignore the ICP (when cranking) and report what it wants, not what it is actually reading just to try and start the truck. I know this is confusing but it will send you on a merry-go-around while diagnosing the problem. Keep your cranking times down to less than 15 seconds at a time, better for your starter and you will see real time PSI numbers. Let the starter cool off a few minutes between cranking attempts. Or if you monitor ICP volts instead of PSI you can crank forever and get real time information, also bad for the starter.
ICP PSI will ramp up very quickly, within a few seconds to well above 1500 PSI on a good rig when cranking. I did re-read all 115 posts to see if anything was missed on this end. With your post #1 you indicated new injectors were installed by previous owner and with all the work you have done my guess is injector o-rings are bad, one or more, causing HP oil to leak and not maintain pressure. HP oil pump's are very high pressure devices but very low in volume, doesen't take much of a leak to reduce their performance.
I understand your frustration just purchasing the rig then this issue. You might need to pull the injectors and check for o-ring damage, not uncommon depending on the quality of o-rings or who installed them.
Edit: If you could put a link to the YouTube site that would be helpful to view the data..
Matt, once again the numbers you are reporting are inferred values from the PCM at the ~ 20 second cranking mark. After a period of time the PCM will ignore the ICP (when cranking) and report what it wants, not what it is actually reading just to try and start the truck. I know this is confusing but it will send you on a merry-go-around while diagnosing the problem. Keep your cranking times down to less than 15 seconds at a time, better for your starter and you will see real time PSI numbers. Let the starter cool off a few minutes between cranking attempts. Or if you monitor ICP volts instead of PSI you can crank forever and get real time information, also bad for the starter.
ICP PSI will ramp up very quickly, within a few seconds to well above 1500 PSI on a good rig when cranking. I did re-read all 115 posts to see if anything was missed on this end. With your post #1 you indicated new injectors were installed by previous owner and with all the work you have done my guess is injector o-rings are bad, one or more, causing HP oil to leak and not maintain pressure. HP oil pump's are very high pressure devices but very low in volume, doesen't take much of a leak to reduce their performance.
I understand your frustration just purchasing the rig then this issue. You might need to pull the injectors and check for o-ring damage, not uncommon depending on the quality of o-rings or who installed them.
Edit: If you could put a link to the YouTube site that would be helpful to view the data..
I understand that its defaulting just confused as to why I'm building damn near 500 psi but it's just not quite getting there. Would even the slightest leak cause that much of a loss in the pressure. I contacted the shop I had taken it to yesterday and the company that redid the pcm. The place that did pcm said that the ipr circuitry is what was bad and what they fixed which before I sent it off ipr was always cranked at 83.9% now upon getting it back it's around 35 to 57% while cranking I posted a video on YouTube named readings from torque pro should come up as the third video that comes up now. So you can see what happens while cranking. I just know if it doesn't end up being a injector boring leak the shop said it gets down to the nitty gritty and can cost me way more than what it's worth to fix the truck.
Matt, reviewed the video and have a few observations:
1. You are no where near the 15 - 20 second mark cranking on the video as viewed so don't think that is the issue.
2. IPR% looks good as it is trying to ramp up HP oil but for some reason it is taking longer than normal.
3. IPW is at .424 ms which means the CPS is giving the PCM good data. This also means the PCM is waiting for HP oil to ramp up and release the IDM to fire the injectors.
4. IPW changes to 3.568 ms as the HP oil is approaching 450 PSI but before it goes way up. This means the PCM is instructing the IDM to fire the injectors. Probably why you have some white smoke.
The slow rise in HP oil could be simply air still in the HP oil rails. Need to get it started to remove that. I'm wondering if you could re-check the actual fuel pressure while cranking and give the results? A simple tire gauge will do the job while someone else cranks the engine. Think you said something like 12 PSI but should be more in the 20 PSI range cranking. Gauges hard to read as kinda small but RPM sounds good in the video.
Sending BuddyBarnes some reps for posting the video ... Thank You !
Matt, reviewed the video and have a few observations:
1. You are no where near the 15 - 20 second mark cranking on the video as viewed so don't think that is the issue.
2. IPR% looks good as it is trying to ramp up HP oil but for some reason it is taking longer than normal.
3. IPW is at .424 ms which means the CPS is giving the PCM good data. This also means the PCM is waiting for HP oil to ramp up and release the IDM to fire the injectors.
4. IPW changes to 3.568 ms as the HP oil is approaching 450 PSI but before it goes way up. This means the PCM is instructing the IDM to fire the injectors. Probably why you have some white smoke.
The slow rise in HP oil could be simply air still in the HP oil rails. Need to get it started to remove that. I'm wondering if you could re-check the actual fuel pressure while cranking and give the results? A simple tire gauge will do the job while someone else cranks the engine. Think you said something like 12 PSI but should be more in the 20 PSI range cranking. Gauges hard to read as kinda small but RPM sounds good in the video.
Sending BuddyBarnes some reps for posting the video ... Thank You !
thank you for the reply and the solid information. I know that the shop tested fuel pressure and it came back good on there end. I will recheck it and see what I get myself. Now my question is how do i go about getting the ol girl to fire up shoot it with some wd-40? To see if that helps it crank over more and fire up?
Matt, please check the fuel pressure before anything else. I'll believe what you say, not the shop. A tire stick type gauge will work fine, 0 - 50 PSI while cranking. Get something cheap as the diesel fuel will destroy it in short time. Have someone crank for a few seconds then press it on there. Use some rags as it can get kinda messy.
I'll never advise another member to use any type of starter fluid, but in this case if it was my truck, and all the work you have done, I would .. but you didn't hear it from me. If you go that route disconnect one of the small wires on the GPR to disable it. Once again, it's your decision.
Report back on the fuel PSI if possible as it and HP oil work together to atomize fuel into the cylinders for proper combustion.
Matt, please check the fuel pressure before anything else. I'll believe what you say, not the shop. A tire stick type gauge will work fine, 0 - 50 PSI while cranking. Get something cheap as the diesel fuel will destroy it in short time. Have someone crank for a few seconds then press it on there. Use some rags as it can get kinda messy.
I'll never advise another member to use any type of starter fluid, but in this case if it was my truck, and all the work you have done, I would .. but you didn't hear it from me. If you go that route disconnect one of the small wires on the GPR to disable it. Once again, it's your decision.
Report back on the fuel PSI if possible as it and HP oil work together to atomize fuel into the cylinders for proper combustion.
I will try and check the fuel pressure tonight when I get home from work
Hey guys sorry it's been a while since posting. I was waiting for the weather to finally break and kind of lost interest in working on it. So today I decided to get out and mess around with it. The fuel pressure is 40psi while cranking so that is checking out good. Now I did notice a couple of the connections for the valve cover harnesses are a little late up and one of the harnesses seems to be missing a pin can this cause my no start issue? I have pictures I will be attaching.
You have two bad terminals, not just one. Inner one is for the injector, outer is for the GP. There's a good chance the two are shorted together, either under the VC or at that connector. In any event, YES, that could cause a no-start. Remove valve cover and inspect associated wiring inside. Replace as needed, should make a HUGE difference.
