hi all please help

my graduate 106 is giving me a hard time :banghead:if it gets enough power to get it going, as i approach junctions roundabouts etc i change down then when i go to accelerate there is nothing i have to rev and rev and it may lurch away very slowly and then pick up i have to keep it in higher gear than need be and rev like my life depends upon it anybody out there know why this is and is it gonna cost me a kidney to get it fixed thanks in hopeful anticipation