[Man of Steel]

A few days ago my blazer died while backing out of my driveway but immediately started back up. It died again later that day while pulling into a gas station. One day it sputtered while driving down the road. I changed the fuel filter and that didnt solve the problem (its never that simple). When I turn the key on I can hear the fuel pump humming and also did a fuel pressure check and its pumping 50 p.s.i. constantly so I eliminated the fuel pump. I'm not sure what to check for next. Any suggestions?