my truck did this, plugged fuel filter! $3 fix. Then I learned the electric fuel pump was barely working on top of that, so another $21. It would idle all day and actually run alright on the slow streets but once I got it onto the freeway, BOG! had to feather it to the offramp and it would pick up again, only to bog again. Id do what nm9 says, bog it and cut it off, then check fuel level.