i have a 150 yamaha that when at wot it slows down and speeds up on it own it will keeping doing this until i cut back to half trottle. i have replaced spark plugs,fuel pumps,had carburator cleaned and also changed rings because it had low copression i taught this may have been the problem no luck i also checked stator ohms it is good, cleaned fuel filters and filled the plastic tank with clean fuel still no luck. can someone help me please
