So I hope I can dig up some ideas from my fellow wakeworlders.
Monday May 4: Summerized my 2007 MC X-1 like I usually do: replaced impeller, checked fluids (changed in October), replaced plugs, hooked up external water supply, etc... Engine ran great with no warnings, buzzers, or BS. I warmed it up and it was on for about 5 minutes. Nothing out of the ordinary happened at all.
Tuesday - Thursday: Spent the week installing a new ballast system in the rear with new fly high bags and new plumbing. I modified the wiring for the stock pumps to completely bypass the timers for the two rear pumps. The KGB pump is still hooked in to the timers.
Friday May 8: Launched the boat and immediately after start up got a loud buzzer with a check engine warning on the speedometer. Messed with the boat a bit more and nothing seemed to be wrong: the engine was running just fine, it had excellent oil pressure, it didn't overheat, the tranny shifted and felt great, no circuit breakers were popped, and there was no vibration or strange noises. I am very familiar with the 5.7L and engines in general but I could not narrow down any sort of probable cause as to why the check engine warning was flashing. Since the boat was run on Monday and the only thing I did since then was install the new ballast system I am wondering if bypassing and cutting the power/ground to the timers would register in the computer. I can't imagine it would. I also could have bumped a sensor or wire when working on the ballast but think that is rather unlikely. Oh and I just remembered I pulled the starter to grease it, but that shouldn't do anything.
Anyone have any ideas? I don't want to take it in to the dealer and pay to run the diagnostics on it to tell me something dumb.
On a side note I want to thank those of you that have posted up information on do it yourself projects; that info was really helpful when designing a new ballast system while 400+ miles away from my boat. Thanks!