I've had the same problem, first occured last April, they changed one engine coil (In cylinder 4). No problems until this past Christmas and I brought it back in and the only thing wrong again they said was the engine coil needed to be replaced. I had the new coil put in a different cylinder and this time it was still in cylinder 4 with one of the old coils. I asked if this is common and the tech said this was only the second time in six years he saw this. I think there is something causing the coil to flip, maybe the oxygen sensor? And these problems would be related. I don't know if this is related but I am having the same lights reoccur.