2004 F350, 6.0 Powerstroke , Auto, 4x4, Crew Cab

To Start: Truck has run great ever since it was purchased.

About 1 month ago, the Turbo would stop producing boost after a hard acceleration or first thing in the mornings. Check Engine Light eventually came on and I took it to the Ford Dealer. Tech found that the VGT solenoid was bad. They replaced the VGT solenoid (3c3Z-6F089-AA actuator) and FLASHED THE COMPUTER.

Now the Truck runs good except At approx 50mph @1800 - 2000 rpm pulling a slight grade (easy pull) engine bucks, Burps, coughs,???. When I increase throttle the transmission downshifts and problem stops. This even happens when truck is unloaded pulling a grade.

I have found MULTIPLE threads with people having this same issue.

Below are some of the most similar threads.

Thread 1

Thread 2

Thread 3

Thread 4

I never had this happen before the VGT solenoid replacement and / or the computer flashed (computer had never been flashed prior to this).

2 Questions

1. Does anyone know how to fix this?
a. Is it the new computer flash?
b. Is it a new design VGT solenoid?
c. Is there a change in the Ford sensor calibrations? Tech did recalibrate the sensors?

2. Will and can a Ford Dealer back rev my computer code?

This is just an annoying problem since I tow a 37’ 5th wheel camper.

Has Ford not figured this out yet?

 

2005 F350 4X4 Turbo Diesel, 20,000 miles

Starts bucking up hills pulling a 8,000 lb. trailer, just below 1800 RPM and doesn't down shift untill about 1700 RPM or I step on pedal. Will happen every time like clock work. I have not taken to Dealer yet, but my ABS light just started coming on, so I will take in.

Milage has gotten a little worse since new, First 10,000 miles I got 10MPG pulling 8K trailer,and 15 mpg with out trailer, the 2nd 10,000 miles I'm down to 9.5 MPG with trailer and 14 MPG with out.

I will post what dealer says and does next week.

 

Mine started doing that and I found out it was my #2 injector which failed. I'd take it back in for another check.

 

Replaced EBP and EGR. Neither Fixed the issue.

 

mine only did it after the Instigator addition.. pulling Heavy load, at 17-1900.. like it didn't want to downshift, once it did, it was fine, but it was definetly not happy. I put the pyro on , turned the "heat" up... and its not so bad.. Does yours have a programmer, or are they stock??? Mine is an 05. with 12k miles.

 

Sounds like similiar problems that I am having. Mine is very rpm dependant. around 1700 rpm while pulling a grade, truck starts bucking & jerking horribly. Ford engineering came out and spent a day driving it and recording data. That was in December. Said they would have a fix for it soon, still waiting. They claim it is a pressure imbalance across the turbo. A flash is required to fix it, however, they did say they could fix it now but would affect the emmissions. So, they can't/won't touch it. The engineers were actually happy to have my truck, and road, they were able to diagnose a problem they had complaints about, but never able to duplicate. On mine, It does it every time, and is getting worse. i.e. different gears, not just OD.