Hello, need help. My 1990 Yamaha 200hp seems to be only running on cylinders 1 & 2. I see spark on all cylinders and my compression is 110- 115 on all cylinders. When I pull spark plug wires on bottom 4 cylinders there is no change in running. When I pull wires on cylinders 1 or 2 it does. It will run roughly at idle and die when I put it in gear.
I have swapped coils and problem doesn't move. Thank you, Gary sick Yamaha