Volvo Penta 5.7 gxi alarming around 4500 rpms

[kaq1219]

I have a 2003 Volvo Penta 5.7 gxi. When I hit around 4500 rpms I get a steady alarm for a few seconds then it goes to a beep and puts the motor into safe mode. If I let the boat sit for a few seconds and put it in neutral the alarm resets. I have replaced the oil pressure sensor, exhaust temp sensor and cooling temp sensor. Boat is not running hot and all gauges are within correct range. Any ideas what could be causing this?

 

[Don S]

Re: Volvo Penta 5.7 gxi alarming around 4500 rpms

Hook it up to a scan too and find out what is setting off the alarm.

 

[BreakOutAnotherThousand]

Re: Volvo Penta 5.7 gxi alarming around 4500 rpms

Don, are you OK?
You didnt scold the OP for arbitrarily replacing parts!!??

OP. the gauge sensors are not the same sensors that trigger the alarm.

At 4500 RPM, I would suspect a knock sensor.
Disconnect the knock sensor(s), see if the alarm stops, just dont run extended periods without those sensors.

Thats what I would try first.