when im cruising at about 60 and accelorate raising my revs to around 2000 rpm i get flat spots and it doesent stop unless i put my foot right into it, or cruise.
Could be a number of things, but do the obvious first, plugs and leads. Do an error code check too, see what codes are logged. There is a link off the main page of this site of the codes and how to do it in the How To section.