I have a 2006 f250 with a 6.0 it has 214000 miles on it. Last week I stopped and got fuel the next day the truck started acting weird it starts fine runs fine no miss no hesitation just once you get up to high way speeds and try to keep the speed the fuel pressure starts JUMPIN up and down and finally shuts the truck off. It starts right back up. It won't throw any codes Iv had the fuel pump tested it was fine Iv now been told it could be the HPOP. Which ford wants200 just to test it. I'm just wondering if anyone has ever heard of this happening it's the weirdest thing. I also found trash in the fuel filters and a pretty bad oil leak on the front driver side of the motor towards the bottom not sure what exactly is leaking I haven't had a chance to dig deeper. If anyone has had a similar problem please point me in the right direction!

 

Moved to 6.0L Power Stroke Diesel forum.

 

What is your fuel pressure reading when it does this jumpin up and down?

 

First off Welcome to FTE. Secondly, do not throw money at it. When the engine is cold it will start fine, Hot and a no start or long crank would indicate a leak in the high pressure system. Shutting off going down the highway and restarting is no indication of a high pressure oil leak.


What oil and fuel filters are you using? Have you owned this truck since new or was it used when you bought it? Previous work done?

 

Are you sure the leak at the driver side front of engine is oil? Fuel pressure regulator can leak in this area.

 

It is not a hpop problem if fuel pressure is bouncing all over, not if ICP is bouncing all over it may possibly be an issue. What pressures does it jump to? Higher or lower then normal? It should be about 55-60 psi and never below 45 at WOT. If it is jumping higher than 60 I would be leaning toward a failing copper gasket on the bottom of the injectors or a damaged injector allowing combustion gases back into the fuel system. If the fuel pressure is randomly dipping when up to speed, I would watch battery voltage, clean battery and HFCM electrical connections and I would also remove the secondary fuel filter and have someone cycle the key and see if the fuel is aerated.

 

I have a bully dog programmer that I can read the fuel pressure in and idleing it reads 4.1-4.5 KPI going down the road at about 45mph it reads 8.5-9. You can get on it and it goes up to 24 and it's fine runs great has tons of power but if you try to maintain anything over about 10 KPI it will run for about 1/4 mile and start to drop to about 3.2 up to the 7s then down to 2 and if you don't let off the pedal it will kill the truck. An as far as the oil I'm not 100% sure it oil but it's dark colored like oil but it makes me think it's not because the oil dip stick read full and it doesn't lose any oil pressure.

 

I just had 2 new battery's put in last week along with a new starter. Voltage reads 13.0-13.1 goin down the road

 

Your Bully Dog programmer may say that is fuel pressure....but that is not a true fuel pressure reading. Unfortunately I don't what it is.....so hopefully someone else can help.

 

See if you can change the units it is displaying "fuel pressure". Fuel pressure I am thinking is actually ICP (injection control pressure), not the same as fuel pressure. The 6.0 does not have a fuel pressure sensor only a ICP sensor. See if you can change "fuel pressure" to PSI and also see if you can get a ICP sensor voltage at key on engine off.

 

Something else, Do you use oem oil filters with the oem cap? If you are using the aftermarket cap with an oem oil filter it will not close the drain valve in the bottom of the oil filter housing. With this you will loose a lot of your low pressure oil, Low pressure oil feeds the high pressure oil pump (hpop). It would run fine until the low pressure and not feed enough oil to the high pressure oil pump then it will perform as you are describing. Watch the IPR% after your high rpm run and i bet it will go to 85% when the pressure starts bouncing around.

Watch this video if you question if you have an oem cap and filter or not.

 

It is the ICP that the programmer shows. I haven't ever changed the oil in the truck I just recently bought it it ran ran up till last week when I got fuel a station I shouldn't the next day all this started.

 

I took the truck to a shop they tested the fuel pressure And the injector everything came back perfect but it's still doing this.could it be bad fuel

 

Hmm..just caught the user name. Nice

 

Your icp would not be all over the place with bad fuel. What is your ipr when the icp drops? Check the icp sensor voltage at key on engine off. Also try unplug the icp sensor and see if it clears it up. When unplugging icp look close at the wiring connection and see if it is oily inside the plug. If so your icp sensor is failing and requires a new pigtail.