I had the same issue a year ago and it turned out to be the cool plugs (The 4 wire pigtail in the front of the coil). It was vibrating loose but not all the way off so it was making a partial connection causing an ignition circuit code. I took a zip tie and put around it where the snap clips are on the plug in to keep the snaps from spreading apart like you would to unplug it. Solved my problem.