I have a 96 explorer with the 4.0 OHV. it started running rough so i changed plugs, wires, fuel filter and pump. it ran fine for about 2 months, then it did it again, changed fuel pump again and it ran fine for a week, it started chugging and was hard to start. now it won't start, checked fuel pressure was fine, pump and filter were good, but no gas coming out of the return line
any suggestions?