[richie rich]

You may have arcing in the coil box that is intermittent look for black burn spots inside the box from moisture if that,s the problem replace with a plastic coil box i had a miss and could not find ran it in the dark garage did not see any thing so i took coil box out and bench tested it and had arcing in the box, black lines. Clean all electoral connections with muriatic acid and dip in water with backing soda and then in plane water and dab of silicone lube