my 79 245 hesitates/stutters when the outside temperatures above 70f and the hotter the temperature the worse the issue is. runs fine other wise under 70f. it feels like its not getting fuel? just jerks a little. does it more prominently when accelerating from a stop but still persists when driving but is not as severe. fuel filter is new, has new rings on the injectors. pump seems to be pumping fuel fine. what could the problem be, what should i look for?

thanks in advance!