mercruiser 5.0 alarm only over 2K rpm's

by Pat
(Indy)

I have a 2005 Chaparral sunesta 236 with a 5.0 mpi and a bravo 3 outdrive. It recently started throwing an alarm (2 beeps every minute) when I go over 2K rpm's. I've taken it to a repair shop and he changed the pressure sensor (it was really the temp sensor) but it still does it. He says there are no codes so it shouldn't do it. It does it immediately when you put the throttle down and it goes over 2K rpm. I know it has trim feedback problems but he said Mercruiser said that wouldn't cause it. Any help is appreciated.
Pat