04 aveo po300 code,rough idle

[Dakota_Don]

ok ty, the engine was replaced who knows when and by who. the head was replaced because it had leaking valves.. so i been working back and forth with the dealer to get it figured out.. seems who-ever did this swap should have swaped the pcv system from the 04 to the 06..we are finally getting it but its a head-ache..