does anyone know / why the reason the spark plug metal shroud shorts out (sparks) on metal base of spark plug?? i have replaced with new HT Leads , plugs appeared to look ok? maybe a gap issue? or the affected 2 & 3 plugs due for replacement??? i did however notice previous owner had replaced plugs with muli-electrode plug Bosch not sure of serial?
Regards
Richard Nicholls.