Electrical faults

Hi 2carpros, I have a1997 hyundai tiburon fx that is running very lumpy lately, I assumed dirty fuel, got quoted 30 bucks for a fuel filter so I still havn't changed it after a fortnight, sort of running better now not so sluggish, anyway today it felt like it was just going conk out upon acceleration, turned around, just made it home, first thing I noticed was sparks coming off the closest spark plug lead end and arcing over to the left to what looks sorta like a magneto? Please can you help me with a diagnosis? P.S. I have been jumpstarting my 4cyl Hilux off it a lot. Hilux battery has 660 cca