i take it the wire colour is brown with a white stripe?

if so this is the water temp sender wire!

mines gone in the same way !

get a new sender screwed into the head!

th thread on the sender unit is 4mm i got 2 brass nuts that screw onto it!
then all u do is put a crimped connector on the wire thats like a round washer then put it on the sender unit and lock into position with the brass nuts !

job done!