Your boat probably never received the recall ECM programming which corrected the soot problem. My boat turned black every time out when I first got it. After the update, the soot is 95% gone.

Either the props are too big or its in guardian mode. What size and kind of props????

Throttle linkage or clogged up fuel lines/filters ect. if the boat has been sitting for a longer period of time?

Since he didn't say there alrms associated with the 4k limitation, it sounds more conventional like props, dead injector, etc. Plus the dog out of the hole statement. Sounds very much like lack of fuel supply at max sticks.

Must've figured it out, or forgot about OSO since there's been no further input since the original post.