1999 DT 150 Stalling

[Sirfishalot]

Hey Guys I have a Suzuki DT 150 than runs great at up to 4800 Rpms. Anything above that it cuts back to idle without any alarms. You can bring the throttle back and it will catch right up and run perfectly up to the 4800 Rpms. I have changed the ECM and run on a portable tank to eliminate the boat from the equation. Where to look next?

[boats.net]

Sounds like maybe your throttle position sensor is malfunctioning. I recommend taking your boat to an authorized Suzuki dealer and have a computer read out done.