I have a 2002 Centurion Avalanche with the Mercruiser 315, I have a whining noise in my stereo when the boats running.
When I got the boat a year ago everything was fine, except the wiring for the amp's looked like a 12y/o did it. So me in my ultimate wisdom decided I needed to clean it up. In the process I disconnected all power from the batteries, I neglected to move the batteries from there boxes and somehow or another the ground cable came in contact with the positive of the battery. Ever since this happened I have been chasing this problem.
Checked all the grounds
Replaced the deck
Replace the batteries
Replaced the alternator
Put a noise isolator in for the deck on the +
Replaced the cap rotor and plugs
Replaced the amps
Anyone have any advice for me, I'm at a loss and am down to replacing the ECM