[interested!]

Hi! , Reading through the history chat , I noticed you mentioned that the spark plugs have been changed , - Question ? - was the engine misfiring before you changed the plugs ,or after ? .
My history , Years ago - my mate changed his spark plugs for new ones only to find he had misfires , I convinced him to put the old ones back in , misfires gone - the NEW plugs were the problem ! , recommend changing the plugs for KNOWN good ones , - just a suggestion! ,sometimes the simplest things cause the most problems , NEVER be convinced that new plugs are blameless .
An old test is to disconnect one plug lead at a time ( at the coil /cap if plugs are hidden ) and run the engine each time and see if there is a noticeable change , thereby highlighting the offending cylinder ( misfire problems ) .