I have my Subaru parked at work in Colorado Springs and the Rabbits have crawled up on top of the engine and eaten the wires.  Missing on 2&4.  Plug wires have been changed, so I'm going to look closer at the coil wires. 

 

Lots of grass and bushes around, I don't know why they like to get up on the top of the engine.  Crazy!

The engine is warm.  Rodents and Rabbits seem to like PVC for some reason.

Are you sure that it's a spark problem and not a fuel problem?  Try pouring a little fuel into the throttle body and see if it runs on all 4. Good luck.

Swapped the coil. problem solved.