So I purchased a 2013 290 8.2 back in May and have been fighting issues for awhile now. I was using a mobile mechanic that finally ended up telling me cylinder 6 was dead. Before pulling the motor I decided to get a second opinion and drove the boat to a Mercrusier certified shop. They found 3 bad plug wires, a bad O2 sensor, bad water pressure sensor and a bad pulley. After replacing them all no more check engine light! They also took it upon themselves to swap out the B3 24p props for some 20p they had. Boat was running 4300rpm with the 24p and fought to get up on plain, with the 20p it jumps right up on plane and reaches 4900rpm with a full tank and two people on boat and stays on plane at a much lower rpm and actually has a higher top speed (the speedo on the dash was showing just past 45 at WOT).