[zarian2]

Hi all first I'd like to thank you all for running an amazing site, I've learned many things that I otherwise would of had no clue about! This is my first post so I'll try to be as precise as possible. Please let me know what other kind of info you may need!

This story is a tad drawn out so I apologize in advance but hopefully will give you enough clues to get your head around it! I'm from Colorado Springs CO, I'm up in Denver Thursday doing some errands, driving around when I see diesel for $2.43 a gallon at a Shell station. Shell has never steered me wrong before and the price was 10 cents lower than the next station! So I pull in and put about 12 gallons into an already 1/4 full tank. Start her back up and all is well.

About 15 minutes later any throttle use at all produces a weird wheezy sound from the engine instead of the usual 7.3 "chug" and @WOT I can only do about 35 mph, 3 minutes after that I can only hold about 25 mph, 1 minute after that 5 mph, I get her into a parking lot and she stalls out. All attempts to restart result in a lot of cranking and no turn over. Noted the tach runs up during cranking. Also noted all dash lights seem to work as usual, ie. the WTS light still operates. There is no CEL.
Walked to Advance and picked up a fuel filter, drained fuel reservoir (noticed the fuel was a blue/green color), installed filter, "primed" reservoir (key off/on 5 times), turned key to start and the darned thing turned over! BUT! It only idled poorly at about 900 rpm for about 60 seconds then died again. Then lots of cranking but no turning over. Noted that during cranking and while it was running poorly for those few seconds there was no smoke from the tailpipe. Checked oil level, noted engine oil level is within limits and HPOP reservoir was 1 inch or so below plug (couldn't be precise as I didn't have a stick to measure at the time) Was getting late and couldn't work on it where I had it parked. Had it towed all the way back to my house in Colorado Springs the next day.
Thursday/Fridays guess: purchased bad fuel?

Saturday: I dropped the tank in the morning expecting to find algae or sticks or a broken fuel pickup or garbage or cheetos or a sandwich or SOMETHING but there was nothing, tank was immaculate! Strainers were clean, pickup was clean. Blew out the return line into a clean jug, was clean. So I ran some fuel line from the pump into a new clean jug of diesel, cycled the key 5 times with the reservoir drain open and cleaned out Thursday's diesel purchase. Noted the pump only fills the reservoir about 60% full during it's exact 20 second cycle (I thought normal was 30 sec but the fact that the pump ran for exactly 20 seconds timed, i don't know) and that the new diesel was yellowish in color. Replaced the filter, primed reservoir and tried to get it to turn over while pulling from the 5 gallon diesel jug. Nothing. Too dark to work on it more.
Saturday's guess: fuel pump? But why did it run for a few seconds Thursday but not today? And why can't I get it to turn over even for a few seconds with clean diesel in the reservoir? :dunno:

So here I sit rummaging forum threads. I do not have AE but have FORScan so can give some basic computer diag info in the morning but thought I'd get the collective brainstorm rolling now. I have an extra CPS that I can throw in but the fact it turned over once and the fact the tach runs up during cranking makes me kinda doubt that. I also have a new Delphi fuel pump that I will throw in tomorrow. I'm only a 2 year old in the world of diesels but I'm an old hat in general mechanics so if you point me at something or ask for more info about something I can probably deliver. Thank you all in advance for any help you can provide!

 

[joebuck]

I would swap CPS ad see if that helps,the fact your tach moves leads me away from your PCM being the culprit,also do you have any gauges to see what ICP&IPR duty cycle is while cranking? Any pool in ICP plug? Also check that the nut on the IPR valve is on and tight,just some areas to start looking at to get the ball rolling hope this helps

 

[zarian2]

I would swap CPS ad see if that helps,the fact your tach moves leads me away from your PCM being the culprit,also do you have any gauges to see what ICP&IPR duty cycle is while cranking? Any pool in ICP plug? Also check that the nut on the IPR valve is on and tight,just some areas to start looking at to get the ball rolling hope this helps

Thank you for the reply. I got FORScan hooked up. With the ICP plugged in the IPR duty cycle is at 64.5% while cranking. With the ICP unplugged I'm getting 32% IPR DC. Also noted that with ICP plugged in there is no smoke, with the ICP unplugged I'm getting white diesel vapor/smoke out the tail pipe while cranking. Still no turn over though! :dunno:

Also noted ICP plug is dry except for one tiny drop of what looks like oil but it could be some sort of sealant.

Does that mean the IPR is toast or ICP or both?

What other information would help in diagnosing this?

 

[zarian2]

So I ordered a new IPR and ICP, fuel pump will also go in when they get here. Is there anything else I should be looking at/for?

 

[zarian2]

Well...

I replaced the IPR and the CPS. Both were kinda grungy looking but i didn't see any obvious signs of damage. Reprimed the fuel and filled the HPOP reservoir back up. Lots of cranking but still no start. Topping off batteries before i try again. Will replace ICP too but it is unplugged at the moment so I should be getting something right? I'm getting stumped and irritated at this thing, what else can it be? I have fuel going through the engine as I have white vapor/smoke at the tailpipe. I should be getting some indication that it is at least TRYING to start but all I get is flat cranking. Clues? Help? Suggestions?

 

[Pikachu]

Plug the ICP sensor back in and monitor ICP voltage and ICP PSI in addition to IPR duty cycle and injector pulse width and RPM while cranking. If you see RPMs on your scan tool while cranking, the cam position sensor is working. If you see the ICP PSI spike up to the 2000 psi range, but the ICP voltage does not also climb, you have a low ICP condition, possibly due to a hydraulic leak or failed HPOP.

The fuel pump timeout is ~20 seconds if the PCM doesn't detect an RPM signal during that time.

 

[zarian2]

Plug the ICP sensor back in and monitor ICP voltage and ICP PSI in addition to IPR duty cycle and injector pulse width and RPM while cranking. If you see RPMs on your scan tool while cranking, the cam position sensor is working. If you see the ICP PSI spike up to the 2000 psi range, but the ICP voltage does not also climb, you have a low ICP condition, possibly due to a hydraulic leak or failed HPOP.

The fuel pump timeout is ~20 seconds if the PCM doesn't detect an RPM signal during that time.

Thanks I'll look at that in the morning. What do you mean by hydraulic leak? I am seeing rpm go up to around 180 while cranking so that rules out CPS I guess. I'll get another cranking live data in the morning to get you the rest of the sensor info.

 

[Pikachu]

Hydraulic leak, as in injector o-rings, etc.

 

[zarian2]

Hydraulic leak, as in injector o-rings, etc.

Oh I see, well hopefully this data gives you some insight as to whats going on. Sorry it took so long, other life issues arose. Screenshot #1 is the first attempt at cranking, next screenshot is the second attempt. Also noted I had almost no fuel vapor coming from the tailpipe today. Not zero vapor, but significantly less. No white cloud for sure.

And since I just realized that the pictures once uploaded are tiny, here are the links to them in G+, fullsize.

Screenshot #1
https://goo.gl/photos/XxnG54gbxMz5EBGn7

Screenshot #2
https://goo.gl/photos/Xr8A1bZUhGoH3VHL8

If the labels on the side of the oscilloscope are too hard to read:
Exhaust Back Pressure
Engine Oil Temp
Intake Air Temp
ICP Voltage
ICP PSI
IPR Duty cycle
Fuel Pump on/off
Engine RPM
Fuel Pulse Width
Fuel Pulse width (PID not used)

 

[zarian2]

I'm going to start pulling injectors on Monday, is there anything I should be looking for under the valve covers besides blown O-rings? I've heard of splitting of the injector needle before. Is this something that can cause the no start, no fuel/oil pressure situation I'm currently in? Thanks again for the help guys, at least its been narrowed to what sounds like 2 possible culprits!

 

[Pikachu]

Looking at the data graph, it appears the PCM is actually sending a fuel delivery command signal to the IDM, even though the minimum ICP sensor reading (according to the book) hasn't been met. The ICP is still way too low for the RPMs and IPR duty cycle reading, though. I'm still leaning toward a weak HPOP or a leak.

 

[zarian2]

Looking at the data graph, it appears the PCM is actually sending a fuel delivery command signal to the IDM, even though the minimum ICP sensor reading (according to the book) hasn't been met. The ICP is still way too low for the RPMs and IPR duty cycle reading, though. I'm still leaning toward a weak HPOP or a leak.

From what I understand HPOP pressure needs to be 500psi minimum to get enough fuel injected is that correct? If so can I assume that since I am at around 450 psi max during cranking, 1 or more injectors leaking (from bad O-rings) can cause the 50+ psi loss? What is a standard reading for ICP pressure during cranking? And is there a rebuild kit for the HPOP or is that a replace-only type of part? In any case I'll get to work on that Monday, thanks again for your help so far. I'll post an update come Monday night.

 

[Pikachu]

Yes, 500 PSI ICP is supposed to be the minimum, which is roughly 1.0 volts. But, you're losing a lot more than 50 PSI. With the IPR duty cycle climbing as high as it is, you should really be seeing 2000 psi plus. I've never seen a rebuild kit for an HPOP, but before jumping into that it would be a good idea to check the injector o-rings for anything obvious. If you pull the valve covers, leave the wiring harnesses disconnected and have someone crank the engine, you should be able to see oil oozing out around an injector if the upper o-ring is bad. When you changed your fuel filter, was it black? That can be an indication of a bad middle o-ring (it keeps oil and fuel separated). A bad HPOP is a relatively uncommon failure compared to o-rings, but it does happen occasionally.

 

[zarian2]

When you changed your fuel filter, was it black? That can be an indication of a bad middle o-ring (it keeps oil and fuel separated). A bad HPOP is a relatively uncommon failure compared to o-rings, but it does happen occasionally.

No the fuel filter was surprisingly clean. I did not notice any residue in the fuel reservoir. I've got an 8-pack of o-rings for the injectors so hopefully I find something obvious once I get those out tomorrow.

 

[zarian2]

OK, well drivers side injectors are out, will do the passenger bank in the morning, had a bunch of hiccups that slowed me down. Initial look shows no particular damage to the four drivers side injectors, a couple of the top (the squared ones) o-rings were shoddy but were not shredded or split and the round o-rings were in very good shape. Copper o-rings were all accounted for and no sign of leaking. Hopefully the passenger bank reveals something a bit more obvious.

 

[STANGMAN893]

How is the oil level and is it relatively clean? Something quick to check but often overlooked. Also had a similar situation with the fuel return spring and housing as the spring wore through the housing. Hope you get it back running.

 

[zarian2]

A bad HPOP is a relatively uncommon failure compared to o-rings, but it does happen occasionally.

Well I think maybe bad news, pretty sure its the HPOP now. After pulling all 8 injectors I didn't see any major leaks. #7, 5, 3 and 1 all had small leaks at the copper washer evidenced by light carbon build up between the copper washer and the lowest O-ring. None of them had blown o-rings or anything else supremely obvious, however.

Picture of drivers side injectors: https://goo.gl/photos/EHd9U2zumZapA71C9
Picture of passenger side injectors: https://goo.gl/photos/a9h6htL34RzvjBYy9

The bags behind each injector are the oil spouts and hold down bolts. Pictures are AFTER new o-rings.

Notes
-Every injector except #8 was a reman and had shoddy upper (the squared one) o-rings. By shoddy I mean when i pulled them they had strips of rubber hanging off of them, like poor manufacturing not post-installation damage.
-#8 was an "AD" injector (thought this was supposed to be "AB"?).
-All 8 glow plugs were BERU and all 8 ohmed at 0.01 - 0.00, good as far as I can tell.

Going to pull the HPOP next to see if the gasket or o-rings on that are shot. After that its a T500 I guess, don't know where else to go with this.

How is the oil level and is it relatively clean? Something quick to check but often overlooked. Also had a similar situation with the fuel return spring and housing as the spring wore through the housing. Hope you get it back running.

Oil level at the time of breakdown was 1-1.5 quarts lower then max, but still at the operating range level on the dipstick. Oil is fairly clean (black of course) and I added more T6 to top it off while I was stuck up in Denver so it's full now. As for the fuel return spring, I havent checked it but I have fuel returning to the tank in what looks to be a fair amount (I did not measure but it is definitely returning.) I'll pull the return line at the bowl and check it out tomorrow.

 

[zarian2]

So a quick update and bump I guess. I got all 8 injectors back in, cycled the engine by hand to get any oil out, etc etc etc its all back together. Did 4 long cranks (30 sec with 15 minute breaks) with the valve cover gaskets disconnected to get some oil back into the rails. Plugged the valve cover gaskets in and did 4 more long cranks (30 sec with 3 minute breaks) and so far nothing. Not even a hint of it trying to start. I unplugged the ICP to see if that helped and honestly it didn't look like it made any difference.

Also, I removed the fuel pressure/return regulator on the side of the fuel bowl and checked that out. It was filthy and had a bunch of sediment in it so it got cleaned and a bb put behind the spring. Still no difference.

Going to try a T500 HPOP once I get mine out this week and if still no luck, I think it's going to the stealership. Honestly no clue what to look for after that!
If anyone has any more clues or advice please feel free to let me know!

 

[RedneckGirl]

Considering it takes oil pressure to fire the injectors, that's what I would head towards next. I had sort of the same symptoms in my '03 after purchasing it. The washer on the drain plug was missing and the truck had lost enough oil that it couldn't sustain pressure and just died. Personally, since you've already done the injectors/CPS and if the fuel pump is putting out what it should, that's the next place to look. Without enough oil pressure to sustain the injectors, it won't run. After a decade of ownership I noticed oil in the valley on top the engine and bought the $55 rebuild kit and knocked that out. I was afraid it was a rear main seal but nope, the HPOP just needed maintenance and the rebuild wasn't all that complicated.

I really hope you can get this truck back to life. Something I do is constantly check for DTCs to see if they will lead me in some sort of direction!

 

[zarian2]

Considering it takes oil pressure to fire the injectors, that's what I would head towards next. I had sort of the same symptoms in my '03 after purchasing it. The washer on the drain plug was missing and the truck had lost enough oil that it couldn't sustain pressure and just died. Personally, since you've already done the injectors/CPS and if the fuel pump is putting out what it should, that's the next place to look. Without enough oil pressure to sustain the injectors, it won't run. After a decade of ownership I noticed oil in the valley on top the engine and bought the $55 rebuild kit and knocked that out. I was afraid it was a rear main seal but nope, the HPOP just needed maintenance and the rebuild wasn't all that complicated.

I really hope you can get this truck back to life. Something I do is constantly check for DTCs to see if they will lead me in some sort of direction!

Ya this truck is driving me crazy but I'm running out of things that CAN be wrong with it. Valley has been dry but who knows, maybe I'll see something once the pump is off. Where did you buy the rebuild kit? Online or somewhere local?