Can you hear the fuel pump prime for a few seconds and the electric throttle body buzzing when the keyswitch is turned on?  Check the 3 fuses and relays on the engine harness near the ECM.

It could be possible that the valve seals are going out. When the engine turns off, some oil stays on top of the heads. That oil can leak down through the valve seals into the cylinders. I believe my fathers 2005 lxi has the same problem.  When we start it up after it sits for a week or two there is black smoke at first and smells rich while it runs for awhile.

Have you had any oil consumption?

I run it at full throttle at least once a weekend. I also do not take it fast unless it’s at a minimum of 120° per per the manual. I highly doubt the dealer did that. To be honest, I’m not the most trusting of dealers in general. They are so busy that they are in and out with boats.

They’re both Atwood bilges I’ll check the wires

2007 vRide w/ LCR 320: Getting a dash display message that reads "ENG ECU - NO DATA OVER 25 SEC".

Boat has been having somewhat long cranks. Replaced starter this morning after getting current one tested that read bad. After installing new starter, boat will not crank at all and dash reads ENG ECU - NO DATA OVER 25 SEC. Battery switch was shut off during starter replacement. Re-installed old starter and same message; engine will not crank. 

Boat ran fine while boarding this morning. 

Where do I start to look? Is there a fuse that popped? If so, where? Really hoping its not the MMDC. 

Thanks in advance.