Hmm... I seem to have the exact problem. I have an 06 Fusion 1,4 TDci with ~85000 miles. Bought the car in July from a local Ford dealer and got a 6 months warranty. I have this issue from the day that I bought the car, but I returned it to the dealer for a 'thorough check' a few weeks ago as it was getting more and more obvious that the car is 'jumping' at around 2000 rpm in the 3rd and 4th gear. Below and above that range and in all other gears all seems fine. Seems great actually :). No smoke, great mileage, ... What they did? Changed the injectors (all 4) under the warranty (2000 EUR would be the cost if I would have paid) which made the problem less obvious, but it's still present - I talked to a friend of mine at Citroen - it's basically the same engine, with the same fuel injection system (Siemens) and he told me they have this documented as a 'hesitation problem' which they sorted out by upgrading the ECU SW. Now - I have the latest SW on my Fusion's ECU, but I think that exactly might be the problem - before 2007 the Fusion had an 'older' version of the 1,4 TDci engine which didn't have an Air pressure sensor (a 'MAP' as they called it), which the newer version of the engine has. I'll be going to another Ford service station soon to downgrade the ECU SW to the 2006 version - hopefully this'll help :). It's a very simple engine and I'm convinced this is a SW thing, there aren't many thing that could go wrong on this engine. I'll let you know if this helped, if you find out something in the meantime, please let me know :)!