98 Tahoe: Stall & acceleration trouble

98 Tahoe... Engine bogs down when accelerating onto highway, from 3 gear on. When step on gas pedal, engine chokes u p& seems like going to stall. Most recently, after this problem started, the engine now stalls at low speeds. After shutting engine off for a few hours, problem went away, but it will come back.

Fuel filter has been replaced. Note: this problem, along with some rough tranny shifting, only seem to occur after AC useage...

Any help/ideas on where to begin would be GREATLY appreciated.

Thx

could be electrical, check your battery connections and alt. output.