1999 130 Saltwater, Limp mode?

I have a 99 Saltwater 130, Idles fine compression is 125 for all cyl. replaced the headgaskets & waterpump, ran fine for about 40 min perfect; start, idle,full throttle. then went into what I think is alimp mode, still will idle fine but wont rev above 2000 rpms. Has had this problem in the past. fresh gas, filters, carbs were clean inside, idles fine and starts in less than 1 rotation.
Need a direction please. sensor, ECM unit?

[bigfish1229]

look at the sensor on the oil tank on the side of the motor.i would bet that is your problem

[jb123]

no buzzer or gauge signals?

No buzzers, pulled oil level sensor out while engine is running buzzer sounded and engin statred to run rough. We have tested the motor in the water 2 times first time ran for about 45 min. full tilt, idle, all throttle positions.(ran purfectelly) Then while under full throttle trimmed out @ 5600 just droped back to 4200rpms. dident miss, no alarms, ran smooth just wouldent go above 4200 brought it back to idle ran smooth, hammered the throttle and it wouldent get up on plane 3200rpms max took about 200 yards for it to plane but it still wouldent go above 4200rpms never missed a lick sounds great.
Last weekend took it out again ran flawlessly for about 15min and started again disconected the temp sensors and the oil level switch with no improvement. Other than that it starts right up and idles purfectly, no missing or sputtering. very frusterating. Please help

[bigfish1229]

just had the same problem on a 200 vmax, would go in safe mode we tried changing computers, and just about all other electrical parts, finally it turned out to be the oil sensor.