It can be any of the connectors causing voltage spikes but a coil drawing too much power is a common cause.

If it where my car and the plug wires where more then 5 years old I would just do plugs/wires and coils as soon as the money was available. The resistance it in the wire goes up and causes the coil to run hot all the time, the coil with start to short internally and it will draw more power. Sometimes the coil fails some time its the ICM but if you don't change the plug wire the cycle starts all over again and there is no way to know the condition of the current coils unless you have a scope handy.

 

I appreciate everyone's help. I changed both spark plugs and wires last week. Spark plugs 5 and 2 which are on the same coil had fuel on them so I'm thinking that's the coil that might have failed

 

I would replace all the coils. It could have been a defective one but if it was caused by high resistance in the wires then the other coils could fail down the road and they may take the ICM with them.