Rough idle

[dawgs]

1998 Johnson 130. Boat seems to run great at wot. But when I'm idling it seems rough and stalls. And also at low rpms the motor shakes as if it missing somewhere. I connected a spark tester and all 4 plugs have spark. I don't know if it's me but it looked like port side plugs sparks are a little weaker. I performed a test. While running I pulled the plug wires off one at a time. When I pulled either strbd side plug wire the motor sputtered and died right away. When I pulled the bottom port side wire it seemed a little worse but didn't die. When I pulled the top port wire the motr didn't change at all

 

[racerone]

You need to start with a compression test.----If you have spark on all 4 then you may have internal engine problems or plugged carburetors.