for some reason, I am not getting ignition from the #4 and #6 cylinders. I have changed out the cap, rotor, plugs, plug wires I am getting fire all the way to the spark plug, but for some reason no ignition is happening in the cylinder. I don't know if the valves for those two are not opening all the way or what. I have great comression, just no ignition. So right now Im just running on 6 cylinders. Please send me your opinions.