I have a 240 v6 j engine that alarms as soon as the engine had started after sitting. The code that the mechanic gave me shows erwt sensor #2 is running hot(223F). I have 2 exhaust temp sensors on each side. I have tried a new sensor in each position 1 at a time. I have also tried unplugging them all 1 at a time and all at once. The code is spn 1386 fmi 3. This engine has 100 hours and is in a 2017 regal 22 fasdek. This code started after I had some misfiring and replaced the plugs and the boat had sat for a while. I am at a loss of the next step to take to try and stop the alarm.