Hey guys, ive tried most everything I can think of to test and observe on this truck. Basically, this is a pure bred stock f-350 four door long bed. 70,000 miles on it. customer never drives it and it just sits in the yard. Because he never drives it it just sits. it's gone probably 2,000 miles in the past two years, well anyway, it's also been three years since he's had an oil change and atleast 10,000 miles. Well he took it out and hauled a trailer last week with it, went three hundred miles, perfect trip, parked it back in the yard with no problems. Goes to start it a few days later and it's a no start. Cranks, cranks, cranks and to no avail. Well finally a day or so later he brings it to my shop saying it started after cranking a little bit and is running perfect and wants me to fix whatevers wrong with it. Fair enough. So first thing I do is change the oil, like I said, it was three years old and ten thousand miles ago it was replaced. that seemed to help a little, changed the fuel filter while I was at it, a little tan but no oil or contamination, water, ect. So I let it sit over night to start with fresh conditions, and its the same thing. Cranks and cranks and cranks and finally it will start to romp, and sometimes come to life and sometimes won't. I plugged in my maximus scanner to watch icp and ipr readings and when I went to crank to watch numbers, it started perfect. ofcourse. So I checked for oil on the icp sensor, no oil there. I started thinking all this bad oil could of damaged the ipr internally or atleast be causing it to hang up, I had a spare one sitting in my console of my 2001 so I threw that in the hpop. let it sit, still has the same starting issue. When it starts, it runs on all 8 cylinders, no glow plug issues, the only code it has is a p1670. the numbers are always checking out right when it's cranking. when it starts, it runs like a brand new truck. I took it out and drove it 20 miles with no issue, a few times now, just to come back to work, let it sit overnight and in the morning it has a real long crank time before it romps to life. Could a CPS be causing these issues? a p1670 is an electrical feed back issue but my scanner is showing rpms on it, as well as rpms registering on the dash. I'm kind of at a loss here because. any help guys? I appreciate it for sure.

 

I also meant to comment and say that after the IPR Installation the throttle response through-out the entire RPM Range was drastically increased though it did not cure the issue. I'm keeping it in there and just going to rebuild his old one and make an exchange. I'm not sure whether the spool nut is causing the difference or the entire assembly together but I'm going to rebuild and keep his old one as a spare.

 

P1670 means the PCM isn't getting the feedback signal from the IDM. Extended cranking/low voltage can trigger it, in my experience. Might consider load testing the batteries. The cam position sensor shouldn't trigger a P1670.

After the initial hard start, will it restart without a problem? Have you checked the oil level in the HPOP reservoir after it sits overnight, before cranking? It should be within an inch or so from the top.

 

I haven't checked the oil level, no, I guess that's my last stop in this deal, I just tried the truck and according to my maximus scanner the ipr % when cranking and romping max's out around 35% on my scanner and ICP psi is up to 2,000 or so. in my head what I think seems to be going on is the high pressure oil pump is draining oil back into the base and and the LPOP system has to prime the pump again before it will take off. This is what initially caused me to swap IPR's because I thought that if it was hanging up some it could cause the HPOP to dump oil back into the base. is there another way for the HPOP to lose it's prime?

 

Yes, a leak in an injector upper o-ring can drain oil back to the crankcase.

 

Okay, is there a way of confirming this? the fuel filter is clean and the oil is perfect on the dipstick. I can do the injector O-rings, if I'm gonna do one, I might as well do all of them, but this is just the first time I'm encountering this issue and want to better understand it. After the truck starts and warms up, it's perfect, start after start after start, until it sits and gets cold again. This must be when the injector o-ring is seeping and allowing oil to return to the base? and it's probably a time issue, not a heat issue as far as to why it starts perfect when hot and bad when cold, letting it get cold is giving it time to evacuate the hpo oil system?

 

Yeah, as it sits, the oil drains from the reservoir, through the pump, out the o-ring and into the crankcase. You can check for upper o-ring leaks (in most cases) by running the engine with the valve covers off and watching for oil oozing out. Smaller leaks can be harder to see, and sometimes it's necessary to pressurize the oil rail with air, or a portapower pump filled with engine oil. Honestly, with the age and lack of use it wouldn't be a bad move to change them all purely from a maintenance standpoint anyhow.

 

Pika, Isn't their a check ball in the HPOP reservoir?

 

There is one in the block, but it's very rarely the problem with an oil drainback problem. 99 times out of 100, it's an injector o-ring.

 

Well at this point, that has to be whats going on. Everything is checking out, front to back and I figured it was something special like this, I've got two of my own, an 02' and an 01' and I've never seen something like this but a little diagnosing goes a long way. I've got a full set of injector O-rings sitting on my shelf. i'll pull the valve covers and get the o-ring's done, and before I seal it back up i'll do the .50 mod on the UVCH's and call it a day. All 8 glow plugs worked good in February so those can wait another year or so. Thank you very much for your help pika, I'll post up in the next few days and let you know how it goes. Other then the injector O-rings, and the IPR, there is no other way for the oil to drain back into the base? and it can't drain back into the LPOP system can it?

 

Maybe I missed it somewhere but did the HPOP drain down overnite? Did not see if you had checked it?

Smokie

 

That's the one thing I haven't checked actually, I'll check it first thing in the morning when I get back over there. The reason i hadn't is because when I first crank it in the morning or after sitting all day the hpop still builds numbers. It shoots right up to 2000 psi or so and desired goes up as well but then I thought maybe that's just what the pcm wants and that those numbers don't necessarily mean that they are actual? Am I correct to assume that or would a drained back hpop system register nothing for numbers for a few seconds of cranking till the lpop primed it? I was going to check it tomorrow before I did the o rings anyway out of interest.

 

Hey guys, I just wanted to post up that this morning I came in to work and checked the HPOP oil level and using the allen wrench I took the plug out with, I measured how far down it was, from the top of the reservoir, to the point of where the allen wrench touched the oil was about two inches. so if there is about an inch of threads the plug screws into, from there on down the oil was about an inch down. I believe the oil is suppose to be about 1/4 to 1/2 inch down from the plug so this is about a half inch lower then it is supposed to be. I'm not sure that's enough to cause this hard start though? Any thoughts guys? I'm putting the injector o-ring job on hold till I hear back from you guys.

 

I believe the book calls for it to be within an inch of the top, so I don't think that's causing the issue. Did it exhibit the hard start problem again when it was cold this morning?

 

Good call. Let it sit all day today and tonight (since your customer never drives it anyway), and then in the morning, execute the process of elimination, as follows:

1. Try and start it. (To verify that it is in the problematic phase of not starting).

2. Check the level of HPOP reservoir.

3. If not below 1/4" to 1/2", then the reservoir isn't the reason why it didn't start.

4. If indeed below level, then fill it to level, even if it only requires an inch of oil.

5. Try to restart it again. If it starts, then Smokiesman is the man.

Then the task becomes why did the reservoir level drop? Delux06 mentioned the checkball.