wanted to share this.

 

Is this the switch that is only used on 75/76 280z's? My replacement engine has the 1-wire sensor in it's place, which I am not using.  Is the function of this 2-wire sensor to adjust the ignition timing during warm up?

On the 1975 the two wire sensor is for the ignition timing during warm up OR on California cars (like mine) to turn of the EGR during warm up. I am pretty sure the 1 wire was for the cooling fans used to cool the fuel rails on later models. The one wire one is the one that can be modified to work since it has a long body that can house the thermal switch. The one that came out (did not work) is very stubby and mostly hollow (there is no room for the aftermarket switch element).