Hi. Have you had any luck sorting this problem. Just bought 2007 2.0R. I've got exact same problem as you have described. I'm in process of changing fuel filter, plugs, air filter etc. No faults showing up on on scanner. My problem seems to be around 2000 - 2500rpm. Like a hesitation sort of misfire. So annoying. Car runs great above or below that rev range. I read a post about someone bypassing the knock sensor or removing it out of the way. They said it cured the problem. But no details on what or how they did it.