2013 F90 Yamaha Misses

[rookyboatman]

My F90LA (new 2013) Yamaha 4 cy on my 24 ft pontoon boat runs good at rmp's below 4000. At 4000 and above, it runs ok for a few minutes then reduces rmp's to 3000 - to 3500. After a minute or so, the rpm's go back to the original level. It does this over and over. It has 75 hours run time. I've put in extra gas additive but it hasn't made any difference. Do I have a filter issue or something more serious in the computer?

 

[99yam40]

probably running lean due to plugged filters or sucking air is my guess.
good way to melt a piston.
monitoring fuel pressures when problem shows up will help see what is happening if those are a problem