first off my vavle seals r Shoot every time i start up my z it smokes out my my whole block lol The car started 2 idol a little ruff so i decided to chang my spark plugs n filter every one had oil around the threads but one of the spark plugs had half the insulator tip missing where u gap it WEIRD RITE? I put new plugs in and now im getting a po300 random missfire code everytime i go up to 2500 rpms or more it loses all power n shakes AND THE CHECK ENGINE STARTS 2 FLASH but it idles so smooth you cant even tell that car is running does any body knows wat this means even what would cause the spark plug 2 chip off like that totaly weird