New to diesels and I am a "backyard" or "weekend warrior" style mechanic (or is that "parts replacer"?).
2006 Lariat with the 6.0
Owned the truck for about 7 months now, every fluid has been changed, always run cetane boost/conditioner. Runs like a raped ape.

Had a no start condition on my truck two days ago. Truck had acted strange twice in the past 3 weeks, thought it was just a fluke. 1 hard cold start, 1 hard hot start.
I read the "no start checklist" but I am severely limited because I do not have my tools with me.
Truck cranks normally but will not fire.
I check oil level, fuel related items and check for codes, blown fuses.
No codes, everything appears normal.
Next thought is ICP sensor.
I check the plug area for oil, see nothing, so I unplug the sensor and immediately try to start the truck.
Truck still cranks normally, just does not fire.
I resign myself to the fact that I have to get it towed to a dealer (NYC does not have many diesel shops).

I call the dealer this morning and they tell me that the first thing they checked was the FICM (checked ok), then they unplugged the ICP, it fired right up. They are doing a few more checks, replacing the ICP and truck will be ready in a little bit.

Was I supposed to wait a few minutes after unplugging the sensor before starting??

They say they monitored the sensor and got some real crazy readings at idle.
Could those readings (given the very sparse info given) possibly point to a slight STC fitting failure, an HPOP problem, or am I just being overly paranoid?

 

Your correct, not enough info. But here goes.
If you have a hpop leak it will show itself after being hot and on a restart, or lack thereof. ICP is possible but not real likely. Check the ficm voltages yourself. Do a search on here for directions. It will take you longer to read the directions than to test the ficm. And no, you dont have to wait a few minutes after unplugging the ICP.

 

Dealership just called and said truck was done.
I'm on my way to go get it. I will have to stop somewhere to buy another multimeter (my 3rd). My tools are 300 miles away.
I have read how to check it, hoping to find a meter, no such luck.
Thank You for the reply

 

Well, I picked the truck up on Friday afternoon. Ran great, sounded a little quieter actually. No issues Friday whatsoever. Started it up on Saturday morning and 3 more times throughout the day, no problems. It did seem like it took maybe 1/2 a second longer to start, but it ran sweet.
Saturday evening, after being parked for three hours, NO START.

Engine cranks quickly, will not fire.
Rechecked the "easy" stuff (fuel pressure, fuel presence, oil presence and flow in housing) and found everything normal. Since the engine spins so fast with a turn of the key, I am going to assume the batteries are ok.
Got out the multimeter I bought and checked the FICM. 49 volts with key on, 48.5 cranking.

Please let me know if I am off track or there COULD be another answer. I welcome any and all comments. Heres what my pea-brain has come up with.

I think that the STC fitting (or other HPOP related issue) is the actual culprit.
When the dealers mechanic checked the ICP, and saw fluctuations, they were the actual readings and not a bad sensor. They swapped out the sensor, probably never verified by rechecking the readings, and called it done. Truck fired, ran, so it must have been fixed.
Heres the weird thing about this, both times I have had problems starting it is when the truck is parked on a hill, hood up, tail down.
Is this just a strange coincidence, or is there some reason for this?
Should I go and let the truck roll downhill and try it on the flat?
I don't see why/how this would matter. Maybe it is hopeful/wishful thinking.

Next time this thing fires (if it will before I have to tow it), it is going on a 300 mile trip to where my tools are. I am going to spend some quality "wrench time" with it.
I have everything together for the CCV mod, egr delete, straight pipe it, and a clean intake manifold standing by. Might as well order the updated turbo drain and the IPR screen kit.

 

Nobody has an opinion on this?
Bueller?

 

Mention the "parked uphill thing" I seem to remember him saying something about that,

Park on a level spot and try again.

 

Apparently I do not have the capability of PM'ing anyone.
Maybe post count related issue??
I will try the "park on the level" tomorrow. Hope it works so I can get it to where I can work on it.
Thank you very much for your help, matty169

 

I will send him here to respond.

 

hey matty thanks for this. try and park the truck nose down and see if it still happens. I run accross this 2-3x now in what 8 years so its a fluke rare thing. if this cures the problem then odds are you have a failed high pressure oil pump. the shaft seal is leaking and alowing the sump to empty while sitting overnight.
there is some more diag to this if your going to do your own work I can cover it after you confirm a few times that your truck will start when parked nose down.
there is an old thread around on this with some video.... if you feel like hunting the search fucntion.

 

If there was a spot anywhere down the hill and onto the flat where I could get the truck parked overnight, I would. I will do this in the morning and give it a go.
Thanks for your thoughts so far.
I will report back what happens tomorrow during the day.

Have a great night guys.