my number 6 cylinder is sparking, but it is not firing! i tested teh coil pack and it was good. i even tried swapping out the ignitor pack, coil pack, and plug, but it still sparks with no fire. does anyone know what might be happening? i think the spark could be grounding itself on the head or something... or maybe the injector isn't ionizing the fuel mixture and its just dripping in teh cylinder... if im right, how could i remedy these?