Engine light fault. There was a bad spark plug and a failed ignition coil. Replaced both the coil pack or spark plug.

I got a fault that said cylinder #6 bad coil pack or spark plug Which is drivers side rear
I replaced the coil pack and replaced all spark plugs. the plug looked fouled & black.
reset the fault and then it came back again, and the after a few days goes away then back again

My car has 65000 miles.
My car has an automatic transmission.

– Engine light fault. There was a bad spark plug and a failed ignition coil. Replaced both the coil pack or spark plug.