1999 5.0 Mercruiser engine dies/misfire

[Curtis202]

Help Please!! I have a 1999 Mariah 202 with the 5.0 Mercruiser Mercarb. I have a random misfire. It also sometimes sputters and tries to die but then it regains itself and continues to run. The other issue is sometimes the engine will just shut off like I turned the key off. When it does die it takes 2-3 times cranking the key before it fires back up. It’s random that each of these things happen. It will run for 5 minutes and have an issue or sometimes it will run for an hr perfectly before anything happens. It does have the Thunderbolt V with the Denso ignition module the engine serial number is OL377919.. the engine only has 215hr original.. I need all the help I can get!!

 

[Scott Danforth]

Look for bad connections between the motor and the helm. This is the ignition switch, MOB switch, harness adapter plug, cannon plug, and the individual terminals on the motor