2003 j90pls Temperature alarm and vibration

[J90PLS]

While cruising at 4500 Rpm I had the over temperature alarm go off, I immediately slowed and put the motor into neutral. I checked the water flow out of the motor it was strong and warm definitely not what I would consider to be hot. After a minute or so the alarm went off and I continued on at a slower pace for a while gradually increasing the speed, everything was good until I reached about 2500 rpm and the motor started to vibrate; so my question is does this motor have some sort of 'limp' mode that it enters to protect the motor after an over temp occurs and if so what needs to be done to clear it?

Thank you in advance

[Joe Reeves]

Yes, when the temperature of the engine reaches a point whereas damage could occur S.L.O.W. mode electronically engages which disengages the ignition of the starboard bank. This has the effect of dropping the rpms of the engine to 2500 rpm.

Either your water pump is failing... OR... something else is interfering with the engine's cooling system.

[J90PLS]

Thank you Joe. I ordered two new temperature sensors and a new water pump kit this morning. Hopefully that will resolve the problem

[Joe Reeves]

Thank you Joe. I ordered two new temperature sensors and a new water pump kit this morning. Hopefully that will resolve the problem

Hopefully you mean "thermostats" instead of sensors? Unlikely those sensors are faulty.