2006 Optimax 150 2 stroke

[corapeake]

Hello all
Engine will start but idle rough. Idle fluctuate up and down for about 3 minute then shut off. Change plug and fuel pressure is above 80. Start right up again and rev engine above 3k and a alarm sounds constantly. Need help. I’ve ran out of ideals

 

[Makomadness]

Hello all
Engine will start but idle rough. Idle fluctuate up and down for about 3 minute then shut off. Change plug and fuel pressure is above 80. Start right up again and rev engine above 3k and a alarm sounds constantly. Need help. I’ve ran out of ideals

Fuel pressure by itself is not a sufficient test. You need to also measure air pressure in the injection system. It is important that the air pressure be 10 psi higher than the fuel pressure. So if air is 90, fuel rail pressure should be 80.
If there isn't a 10 pound difference and you do have adequate air pressure you may have a bad tracker valve. If air pressure is low in general you may have a compressor issue. Check the condition of the air compressor filter if it hasn't been changed in a while.

When you get the alarm above 3000 revs is the motor in gear? It should not be in neutral and run at high revs. That will cause an overspeed alarm condition.
What gauges do you have