Reduced power

[Mharrington]

Mercruiser engine serial 1A614547

while out at 3900 rpms alarm sounds reading says reduced power. When I go in neutral alarm goes away get back on plane code comes back in about 10 mins.
closed loop cooling
temp is 167
water psi is ok
oil pressure is ok
in the driveway it’s pumping water out at a good rate

im at a lost what’s causing it

 

[alldodge]

Howdy
Thanks for the SN, have a EC motor

There is a In-Gear switch on the shift plate. If the PCM thinks the drive is in neutral it will sound the alarm saying reduce rpm.

The pic is for an Alpha drive so it has 2 switches, your Bravo would have only the one. Disconnect the switch and see if the alarm stays OFF. If it does then it needs adjusted