Yesterday I'm driving on the interstate, i get on the gas in 3rd gear from about 4k and right around 6500, acceleration just stopped and it stayed at around 6k. The next time I drove it, it didnt happen again until this afternoon going to lunch. Im reving from lower rpms, not suddenly stomping it, so I'm not really suspecting a problem with the accelerator pump or anything like that, although I could be wrong.

To be safe, yesterday evening I changed the cap, rotor, and wires (plugs have about 3k miles on them) and air filter. The car is stock but the belt has been removed from the air pump.

Any ideas? Thanks in advance.