Ok so I have a 2011 250 SHO with about 8 hours on a brand new powerhead. Yesterday I take it for a run. It fires up and sounds fine. Hops up on plane no problem...runs for about a minute and starts cutting out. I can left off the throttle and come back to an idle. Then I can get on it and it will come out of the hole great but cuts out after a minute or so.
Seemed like a fuel issue to me. I took it to the dealer and he is getting a knock sensor code. He's trying to confirm with a Yamaha tech but if it's the sensor itself its a big job...as in pulling heads and thousands of dollars.
Any thoughts?
Here's the one kicker. I had the boat at a much higher elevation yesterday than past trips...normally fish around 2300' elevation and I was at 4800' yesterday.
I run 89 octane with ring free.
Thanks