Man I hate when you have to keep chasing a problem . Sounds like you have done everything I would do so ill throw something out there just for the heck of it. The pick up coil is triggered by two spots on the rotor,stator or whatever they call it. One for the left cylinder and one for the right so maybe the trigger point for the right cylinder is not as efficient or is somehow hindered from translating that magnetic pulse to the igniter.
I am really reaching here and have never run across anything like that before but when everything else is doing what it is supposed to do, that is really the only variable left.
