F650GS 2008 issue

Hello

First time to write but I have been reading for some time and introduced myself in an other thread. As said I am an owner of a faithful F650GS that brought me already in Romania, Greece, Montenegro, Albania, Gibraltar, Portugal, Spain, Italy etc ... Always with the tent and sometimes alone.

Unfortunately not everything stays good forever, in the youtube link below there is a strange problem which I've been having for a while but can't seem to fix. It's actually only when idling that the cooling water goes from 0 bars to completely full. When driving it is nicely in half. I recently had my coils and battery replaced for another problem and it seems to be slightly better but it's definitely not gone.
If anyone has any ideas, very welcome! Thanks in advance !

Also the sensor cooling water, that golden thing on the block has already been replaced.

https://www.youtube.com/watch?v=FOi9ood1kW8

Hi FreddyBE. Is there a loose connection on the water temperature sensor that only shows up on tick over?????

I an sure someone with more knowledge than me will be along soon!

Thanks for your answer David! Any chance you would know how to check ?

best

Frederik