Hi, I have a 76k mile unit. It is a middle east speç-d model without dpf and it can run on high sulphur fuel. last year I had to change the hpfp because of pressure sensor problem. My mechanic found grass straws in the pump! There was also a lot of grass in the tank (maybe someone has misunderstood the concept of biofuel). Tanks now cleaned.
Now, when I first start the engine and take off everything works as it should - good power. However, restarting a warm engine there is a delay in acceleration. I press the pedal to do a normal take-off power and engine lose power - I continue to press the pedal for a few seconds and suddenly engine kicks back in. Then it works normal until the next time I turn it off and restart. During the delay I the engine rpm goues up and down very slightly until it kick back in. My mechanic has tried to adjust this via the IDS but problem remains. He now suggests it could be a problem with the EGR valve and recommends a change. Can anyone help with a second opinion? Thanks

 

Any change in rail pressure when this is happening? Its very possible there is an issue with the egr valve, but you say it didn't come from the factory with a dpf... That would lead me to believe that it probably doesn't have an egr system either. I have seen a few 6.7s from south America that do not have a dpf or egr from Ford either.

 

Thanks for your suggestion. So I need to hook up a scanner and take the car for a drive. On the attachment is a picture of what my mechanic call the EGR valve.

 

That's the throttlebody that is used to control airflow into the intake. It really doesn't do much on a 6.4 besides restrict airflow...........

You do not have an egr system on that truck.
This is what it would look like if you had egr coolers, note the valve to the right of the part you have shown in your pic.

 

It looks like it's time to have a serious talk with my mech (maybe ex-mech). Thanks for the help. Fuel presssure may be the more likely problem and I guess that it will then be a problem with the hpfp which I installed less than 6 months ago. It is an original part so maybe there's warranty.

 

Did you ever resolve the problem? I am having the same issue but after every startup but no one can figure out why. It all started after fuel contamination with water. Thanks