Temp gauge crazy

Yesterday temp gauge shot up to full (after 5 min drive) and gets mad fits of jumping up and down.If you turn on ignition it goes up full.To be safe i ordered a new sensor yesterday
and while driving today i can hear a strange noise behind dash gauge area.Will investigate in a minute,just wondering are these symtoms of a faulty sensor?Cheers

Ok fitted new sensor and still no change,when i turn on key it goes straight to max.On closer inspection 1 of the wires has a bit of insulation missing and the
wire is exposed but not broken.When i wiggled it today the needle started jumping on the gauge.Anyone know if you can buy the clip and wires new anywhere?

rodent damage? the easy/quick fix would be cutting out the damage section, soldering back together and insulating tape...hopefully that is the only place