Have a 2005 s60 T5 that "stutters' between 2500 and 3000 rpm when under moderate to hard acceleration. The car has 114k. I've done a tuneup - replaced plugs, wires, coils, air filter. Recently replaced a faulty TCV. Had the dealership check for codes and they can find nothing.

Other than the hesitation between 2.5k and 3k the car drives great and still gets 29mpg on the highway, so I don't think it is the turbo.

Has anyone had the same problem? Any ideas?

 

What plugs did you use? These cars seem to only really like the OE Volvo plugs. Also may want to look at changing the fuel filter if it hasn't been changed yet.