Thanks for the input. Sorry for late response as I just had back surgery and was down and out for a bit. Seems the 2 wire sender controls the gauge. After replacing the sender with an autometer sender the gauge was still reading in the 210 range. Checked it with an infrared and it was around 165-170 so at least I know I’m not over heating. I unplugged the one wire sender and gauge was still reading 210 then I unplugged the 2 wire sender and alarm went off and gauge went to 0. So I’m not sure what to do now. I thought the 2 wire sender was for the ecu and the 1 wire sender was for the gauge. Well not on my boat lol. Maybe autometer has the 2 wire sender to match the gauge?? I am at a loss. At least I know it’s not over heating but I would really like the gauge to read correctly?? Any help is always appreciated

thanks

Your assumption is correct... The one wire port side temp sender is for the gauge.. The 2 wire starboard side sender is for the ECU.
I don't know whats going on with your setup.. The only thing I can think of is you have a digital temp gauge that is using the ECU signal and the 1 wire sender isn't being used anymore??

On another note... Hardin sells a temp sender specifically for Livorsi gauges, so I wonder if they use a different resistance range than what you have..
https://www.cpperformance.com/p-1307...si-gauges.aspx