I had a problem like that on the plug wire from the coil to the spark plug The wire had a small break in the insulation and it would mis-fire on occasion. Took for ever to find it, I finally opened the hood at night and saw the spark being bled off.

Let us cross over the river and rest in the shade of the trees
Stonewall Jackson
Hug your loved ones often, Life is short even on its longest days.
I don't see the glass as half full or half empty. I just finish it and order another.