wont run over 10 mph

[Mariojosh24]

Hi I'm new at this and not sure how this works. I have a 2005 Yamaha 150 4 stroke motor that is acting weird. I took it out this weekend and it didn't want to go over 10 mph. It also sounded a little louder than usual, like it being forced. Any ideas of where to start checking before I have to take it to a mechanic?any info will be highly appreciate.

 

[johnnybgood]

I had a 60 hp johnson 2 stroke with carbs and it would act like this, the fix was all ways clean the high speed jets. Having the same problem with my current 70 yammy 4 stroke (no cabs) fuel injected and i am at a loss as to how to fix it