1993 4.0 V6 Truck will not start. Have replaced fuel pump, filter, spark plugs & wires. New starter, air filter. Has a good battery in it. Checked all the fuel injectors and they are fine. Before it would start but idle real rough. It would go down the road and it feels like its miss firing and stall. I've been told something with the EGR..is it the valve maybe a sensor? Could it be an o2 sensor? Mass air flow? Any input would be greatly appreciated. I'm stumped and have dumped to much money in it and its not fixing a thing lol.