I just bought a 2003 26' sonic prowler with a 496 mag ho. And of coarse all was well for the sea trial, no problems. This past sunday the wife an I take it out. We went prob 17 miles out the C&D canal to the bohemia river with out a glitch...Then I start it up 4 hours later an we head back an we hit some semi rough water an it just shuts off going 55mph. So I manage to get it out of gear an started back up with out a problem, we go a few more miles an start to hear the infamous 2 beeps per minute I've read so much about. Then it shuts down againa few miles later. The drive oil reservoir was full, oil pressure and engine temperature were good an manifolds were both cool to the touch. Just kinda confused because I dont remember hearing an beeps before i shut down the first time almost like its a bad key switch or lanyard. Anyone had a similar problem?

You're probably going to need a scan tool. You may have unseated a sensor connector in the rough water so you could begin finding and checking those.

You wouldnt happen to have a scan tool would you?

Simple stuff first. Check drive lube

You've just bought a nice new boat with a nice engine, so complete the equation, spend the $400 and get yourself the Rinda scan tool and keep it on the boat, so when things like this pop up you can give it quick scan and isolate and fix the issue without a lot of guessing or parts replacing. You can blow thru $400 in wasted parts and labor without a scan tool diagnosing problems on these electronic efi engines. I think everyone who owns a newer ECM controlled marine engine should just have a scan tool as part of their boat gear.

Best Regards,
Ray @ Raylar

I do, but I live in Maryland, not Delaware. Like Raylar says they are a smart investment, comes in a nice carry case and are small enough to carry on the boat.
I would also suggest installing a SmartCraft gauge on the dash. Best 100 bucks I ever spent.

Potential iac problem perhaps? Not the normal symptoms but I know there problematic.

Thanks guys I'm ordering scan tool today. I'll post my findings when I get it which is hopefully in time for 80 degrees Sunday. I have checked the lube any one with any sense checks fluids before leaving the driveway. Other than that he boat was awesome