SSCamaro00

my car codes for misfire in 6. i replaced all the plugs and wires plus the coil for 6. still SES. car has loose of power. i had a tune done to my car when i had a bad o2 sensor in bank to sensor 2. replaced that after tune car still running bad. i unplug the injector to 6 an no change in the motor. the light is on for about a week. ses light would go out an them come back on later that day. when the light goes out car runs perfect. i need to find what the problem is. have plans on going to the track very soon.