Need help finding out if I have a electrical problem

What is your question?

My truck runs but wen it gets hot it spudders but the car stays running but I have no throttle but it comes in an out meaning I push the gas but it won't accelerate an then I'll suddenly get power n lose it I have to shut the car down for at least 20 min or so just for it to be able to drive fine I've already replaced the batt like three time just changed the alternator n I still have the problem