17 195open rough idle

[Coltman45]

Hey guys long time!!
Last season didn’t get the boat out much. Had to replace an oil pressure sensor. Got it out to run it this year had to replace o2 sensors and exhaust temp sensor. No codes now but boat will not idle properly, also stalls. It’s the 200hp supercharged motor. Any help is greatly appreciated

 

[Luc Lafreniere]

Start with spark plugs. How old is the gas?

 

[Coltman45]

Had gas sit for a few months, half tank. Topped it off with 92 before trying to take it out.

 

[Luc Lafreniere]

A few months probably won't matter. So likely not the fuel.