code po 300
 

I have a 96 Dodge ram 1500 5.9l I had code po 300 come up( Random Misfire) and i was wondering what would cause that code other than
Plugs, wires, roter, distributer cap, and coil. I have changer and or checked all of these and it has not resolved the issue. we also cut the cat off to see if that could some how be the issue unfortuantiallyit was not. The truck will stat and run great for about ten minutes and then it will fall flat on its face, it will move at about the max speed of about ten if im lucky then it will stall and not want to start. any and all suggestions or ideas are welcomed, dont hold back I am at wits end and am looking for a new take. Thank you

plugs, wires, rotor..
severe plenum leak (lean and/or burning oil) are you fouling plugs ?
coil
crank pos sensor, cam postion sensor, throttle position sensor.
o2 sensor (causing too lean or too rich). likely has more influence when fully warmed up and in closed loop mode. this might be your problem.

weak fuel pressure or stopped up fuel rail. check pressure.
faulty injector
cracked head - do a compression check.