Curious sensor

[red griff 500]

Anybody know what the brass sensor is which is screwed into the inlet manifold at the front of the engine. It’s a brass nut (about 222mm A/F), has a single brass threaded post onto which is fixed a single solid wire (i.e. not multi-stranded) via a nut.
I found it last night and am curious to know.

Steve

[spend]

I'd guess that if you disconnected the spade terminal your water temp gauge would not operate.

[red griff 500]

red griff 500 said:

It’s a brass nut (about 222mm A/F),

Whoops, finger trouble- that should be 22mm, not 222mm.

[starmist]

Yeah, sounds like an earth.