i have a 06 f250 super duty w/ 6.0 no mods . engine misses when acc. normal and when going up hill. tried injector cleaner and new filters nothing changed . the less fuel in the tank the worse it gets. truck starts fine, idles fine, no check eng. light or warning lights and it runs like a champ at full throttle

 

Sounds like you might have a injector problem. A scanguage could eliminate other possible causes and help you narrow it down. Others will chime in and get you going in the right direction with it.

 

check your fuel pressure when the tank is near empty. you may have something like a missing / broken pick-up screen if it worse on low fuel level.
check ficm voltage and injectors for possible related concerns.

 

thats kinda what i was thinking, my plan for tomorrow is to check the fuel pressure and the pick up screen. thanks for the advice.

 

i just bought a 2003 F250 with the 6.0 not knowing anything bad about the engine. On the test drive it drove great. I was going about 40 MPH and got on the highway. i floored it to see what she would do. from under the hood i heard a whine (not the normal turbo whine). It sounded more like someone squeezing a cat and it screamed as my wife described it. It normally happens around 2000 RPM with about 6-7 pounds of boost. The dealership told me they would fix it, and i go on vacation on the 11th. Anyone have any ideas? FYI it has 155,700 miles, and an edge juice attitude programmer. Which i keep set on mileage. It does not do the noise when its cold, but after it warms up for a few minutes. A friend of mine who is a diesel mechanic for the army mentioned turbo bearings, but apparently its a sealed turbo and i cant just change the bearings?

 

belt is slipping on the fan pully. I would also looking at ect/eot and make sure you dont have an issue there too.
second guess is a cracked y-pipe.

 

i just replaced the belt on monday, the fan pulley had no bolts in it so i added 4. the pulley was moving around on the shaft and caused the belt to start coming off other pulleys and shred. what is this ect/eot you mention? i'll take a look at the y-pipe but i think its fine. you mean the y-pipe after the turbo correct?

 

ECT/EOT = Engine Coolant Temperature / Engine Oil Temperature. It can be an indicator of oil cooler performance. They get plugged up with debri/goo from the engine coolant used to maintain engine oil temperature at an acceptable level. It's one of the weaknesses of the 6.0 engines. I don't know if the Edge device you have gives you gauges, you may want to look into a Scangauge or other device that you can program to give you those and other engine performance parameters. They go a long way to preventing major issues.

-Mark

 

Mark, Yes the edge shows me EGT, EOT, Trans temp and boost. It is also able to pull my DT codes and right now i have none. yet this whine happens when it revs over 2k RPM until i let off then it instantly stops. my original thoughts were turbo bearings or an air leak by the turbo. turbo works properly, and i cant find an air leak anywhere, not even on the y pipe

 

radiator cap maybe?

 

radiator cap? it makes a squeal when its moving and it revs over 2000 RPM. if im stopped and in park and rev it up theres only the turbo whine. it did this on the test drive, mind you ive only had it for a week and the dealership said they'd fix it. i would like to figure out what it is so that i can give them an idea as to what to look at. my wife said it sounded like someone squeezing a cat and the cat screamed. as soon as i let off it stops. theres no slip from the transmission, and no lag from the turbo while it does this noise. i know its not normal having a friend who has the same type of truck and his does not make it.

 

it can do it. they sound like a tea kettle when they vent
try the search function for radiator cap. youll see.
maybe a upload of a sound bite would get you more then a guess.
then again sometimes im as clueless as the next guy

 

sorry to hijack the thread, but.......... there is a cat in there...... who knows? lol. tee-hee-hee. ok, i'm done.

 

The first thing I'd do is get rid of the Edge and see what you have. The Edge is also a known torqueshift tranny killer.

 

its not a tea kettle sound its a deeper pitch. i'm going to drop my programmer and see what happens today. thanks for the help so far. i'll let you know what happens when i drop the edge.