I have a 2001 Forester with almost 60,000 miles and the car has recently become very jerky at times. The check engine light flashes and then goes solid. The codes stored are P0302, cylinder 2 misfire, and P0304, Cylinder 4 misfire. Initially, the jerkyness would only be for a minute when the car was first running during wet weather, now it seems to never go away during any type of weather. When the car was running rough, I popped the hood but didn't see any sparking from any of the wires. I sprayed a fine mist of water on where the spark plug wires connect to the coil and I saw a lot of sparking on the cylinder 2 and 4 wires. It was right at the junction of the spark plug wires and the coil. Is this likely bad wires or a bad coil? Any other ideas?