"I have a 2005 Yamaha 115 hp four stroke that stutters mid-range between 2600 - 3000 rpm. Runs fine above and below this range otherwise, but just goes to pot in the mid-range band. Has new plugs, fuel filters have all been changed, everything looks great otherwise. I have even been making sure that the primer bulb in the fuel line is full so that it can't be starving, which would be evident as it operates fine above and below these RPM's. This started back in June and is inconsistent"