Johson 9.9 Full throttle problems

[The big fisherman]

I have a 1995 Johnson 9.9 and the problem is when you start up it always fires right up, then you get going and the engine will rev out fine and run full throttle. It will run like this for awhile and then it just shuts down to about an idle. It never misses or anything. We have tried a new fuel line, different tank, new plugs. Any one have any other suggestions. Had at a repair shop which they put it in a tank for a few hours and it never does it. Only seems to do it when it is in gear. Many times it will go almost an entire day on the lake without doing it, then when you start back to load up you are only moving at an idle. Runs great even when it does this just won't rev up.

 

[R.Johnson]

Re: Johson 9.9 Full throttle problems

Sounds like it is dropping down to one cylinder. When it does this, pull a spark plug lead, to find wich one is, or is not firing. Probably an ignition pak going bad.

 

[fireman57]

Re: Johson 9.9 Full throttle problems

R. is right. Mine ran fine and got me back to the ramp on one cylinder. Just ran slow. pull a plug wire when it does this and you will know exactly which pack is bad.