03 malibu random miss

My malibu will run fine and then when idling seems like it goes completely dead for a half second and then fine again. It really does this after being on highway at speed for a while and then stopping. No check engine light. I use top tier rated gas, car has 44000 miles. Intake gaskets have already been replaced( under warranty). Replaced dirty air filter seems to have helped some. Does anyone have any ideas

Only 44000 miles.. Wow.. I would check your plugs and wires.. Failing that, check your coil packs, allthough this should cause the check engine light to come on. Have you checked your PCV valve recently?