Hello Scotty, i am really confused why my car an Ford Focus 2005 mk2 109hp diesel with DPF has problems accelerating real strong. The car runs really well until 2500 rpm, after that rpm if the acceleration is stepped hard the car will stop responding, the revs will drop until idle and then die. the car was tested and the only error was a faulty glow plug and an error for interrupted DPF cycle. I have to mention the problem was more pronunced in the winter time, now in spring it rarely happens in the morning and in the night when it is a little chilly. What do you think it is?