I'd like to offer a friendly advisement regarding the potential mis-diagnosis of ignition coil failure. I was receiving misfire codes for one cylinder, so I first unplugged the suspect coil to note any difference in running. When there was no difference, I was pretty certain the coil was bad. I then unbolted the coil to check if it was an oem Lucas coil (it was) or an aftermarket that had been previously replaced. Upon inspection, I noticed a small half inch crack in the rubber boot. I decided to grab some electrical tape and wrap around the crack to see if it made any difference. I re installed the coil and fired up the engine. The misfire was completely gone.

The good news is the rubber "boots" are available separate from the coil for $15 @ rock auto and numerous other stores, including Amazon. So before you go out and unnecessarily spend money on a replacement coil, inspect your rubber boots for any cracks or thin spots.

The rubber boots separate from the coil body by simply pulling them apart. Be certain to grasp the rubber boot at it's highest point right next to the coil body when pulling apart to prevent ripping the boot. I drove my car for a week with only electrical tape whilst I waited for delivery of the new boots. It ran perfectly.