Engine problem 1997 z-24

My 97 cavalier z-24 engine light is on and blinking, engine runs rough, cheched plugs, cylinder 3 &4 were jet black and 1&2 were fine had an engine code of p0300 any suggestions

P0300 on your 2.4L is a misfire code. I would take the coil assembly back off and disassemble-inspect. Sounds like you have a burnt coil or housing or boot issue. Sometimes you can see where it was arching-burning by black carbon tracks.