last week bout 96 baja 252. ran idled great. made 5 mile run to dam 1/2 -full throttle entire way. ran smooth responsive. swam 2 hours. came back same style. swam another hour. started idled boat 5 minutes no wake then full throttle to plane then back down to 1/2 planed and level then boat dies. will turn over but only hit a few cylinders and will never acheive an idle. other forum says vaporlock??? engine serial is of778151 if i am correct it is a genv 7.4 lx mpi. not positive. have no owners or service manual for boat. downloaded wrong one and cant find correct manual. didnt see any water in fuel seperators. no fuel in vacume lines from regulators??? PLEASE HELP SOS SOS SOS

boat started instantly the next morning like nothing had ever happened

vapor lock,weather is changing the next few weeks to lower humidity and temp,,when you stop let boat idle for 10 min or so with hatch open and blower on it will help.when you shut it off to prevent heat soak..very common issue .nuthing to due with water..

Vapor lock, if I am not mistaken you have a VST tank next to the ECU also. Merc. had a lot of problems with that setup, which I can assume they eliminated for that reason. Some of the parts to service them are not available anymore either. As copperhead asked, did it start the next day without any problems? I'm guessing it did.
If it happens again and if you have the vst tank, there is a plug on the VST top housing that you can remove to relieve the pressure and it would probably allow it to start right up. Ask me how I know this! It got me home many times.

Yep, vapor lock.