you have any engine codes? or acess to a Scaner?

when it does this hesitation, keep your foot on the gas and press the brake very lightly... this will unlock your Tq converter if the hesitaiton goes away you can get a better idea of the source of the prob.

Also disconnect the battery for atleast 30 min and let the computer reset. its possible you had spark or fuel issues and the computer adjusted to them.... also i would recomend changing your fuel filter if you havent lately.

could be KR issue (93 will help this but need to find the real cause)
could be a worn TQ converter (needs replacing)
could be a MisFire (check grounds and wires and proper gap on the plugs)