I have a 2004 F250 with the 6.0 and 167000 miles on it. I have had it for about 3 months. It ran fine when until about 2 weeks ago. When I start it for first time of the day, it will start and idle fine. The problem comes when I get to the hwy, and try to takeoff it's like I am not even pressing the go pedal for a few seconds then it will takeoff. After the first time this happens it's fine until the next day. I've changed the fuel and oil filters with Motorcraft filters and I used Motorcraft oil. I have a Bully dog tuner set at Tow. I don't have any CEL on. Any help would be appreciated.

 

How long have you had the Bully Dog on? Take it off and see how it runs. Also check EGR valve it may need cleaning. There is also a low power page in the tech folder with lots of info.

 

I would scan for codes, it is possible to have set one without a CEL. Also load test the batteries. Be sure to disconnect one of the cables, a good battery will cover up a bad one because they are wired parallel. If that's all ok, I'd go back to stock tuning until the issue is sorted out. The Bully Dog has a bad rep for being hard on the transmission in these trucks. After that, it would be time to monitor boost and VGT solenoid with a monitor that reads live data to check turbo. And ICP/IPR to check HPO system. And fuel pressure may be an issue. Does it have a update ( blue spring) in fuel pressure regulator?

 

I have had the bullh dog pup about 2 months, I do find sometimes it does shift hard.
The egr had been deleted already with a sinister kit. I'm not sure about the blue spring kit. Never heard of it until today, what are the benefits.

 

stuck turbo?

 

Blue Spring raises fuel pressure. It's best to test first but installing the kit isn't going to raise your pressure too high. Check the tech folder for part #'s and details. It is just a guess (as I think cheezit was pointing out ). best to test, find the problem and repair.
Good luck with it and welcome to FTE!

 

I put the factory tune back on and checked for codes with the bully dog, no codes appeared. I didnt get to drive it yet but I'll try that and go from there. Thanks for the help, and suggestions.

 

Hopefully you checked for codes before changing tunes, which will erase any codes. Drive the truck stock and see if it responds better/worse and recheck for any codes.

 

I didn't know that I changed then checked for codes. Well I guess I have a lot to learn. I'm just getting into tinkering with Efi and deisel. My other toys were always carbureted.

 

Just wanted to update all. I went back to the stock tune and the hesitation when cold improved a little. I rechecked for codes after driving it about 100 miles but still no codes. I did read in the forums that when changing the oil to only put 13.5 to 14 quarts, I changed the oil prior to reading this and put 15 quarts, I will try to remove 1 quart and see if that helps.

 

My last oil change was 15 qt and I
did not go over the full mark.
Did you remove the filter before
you removed the drain plug?
You want to do it that way to get
as much of the old oil out as you can.
Under the filter is a drain that is closed
when the filter is in place. Unscrew filter
cap and that opens the small drain and lets
the oil drain back into the crankcase. After that
you remove the oil pan plug and you will get
as much as your going to get.
FYI
There is a hidden 2qt give or take in where the oil cooler
sits that also feeds the HPOP that you won't get out
with out a top tear-down

Sean