when piston no1 is up is the ht lead (no1)on that one piston also check with all the plugs out in the corrct line up that they are sparking and you havent got a dud plug make sure they are away from petrol tho also is the car back firing or just missing
what have you done to the engine ie cam change or headgasket sorry for all the questions just bugging me as i want to sort it out lol