Which cylinders do not have spark? Normally those motors have 2 switchboxes. One provides spark to cylinders 1,3,5 and the other provides spark to cylinders 2,4,6.
Swap the stator leads on switchboxes, if problem goes to opposite side the stator is bad. if stays the same switchbox. Check the bias circuit as the one working can cause the one not working to not fire. If bad one firing is bad and the one not firing is good. This is why factory states to replace as a pair.
Confusing huh???
