Ok well this is my first post on here so please bear with me. I have a 1990 force 50hp model 507X90D. I had the boat out over the weekend and noticed I was way under-powered. My first thought was a fuel issue as the motor sounded fine and was running smoothly. I had good fuel and made sure the tank vent was open. I also removed my in line fuel filter just in case. The issue still persisted. I the thought to check spark. I have the blue ignition coils (2) and the blue CDI (1). I had great spark on one and very weak if any spark on the other pack. Tried new plugs and no improvements. I then swapped the packs. The pack with no spark before now has spark and the one with spark before doesnt spark anymore. The thing I am wondering is do I have a bad pack or a bad cdi ? I was initially thinking pack, but now am not so sure. Could one side of the CDI be working fine and the other is bad ? The CDI and one pack was just replaced about a year ago. Any thoughts or input would be greatly appreciated before I go putting more money in to this. I have a Clymer manual but its not very helpful in this situation.