Thermostat Sensor what is it called on top of the tstat housing
 

This is a single wire sensor, what is it called and what is it used for

Thanks

David

pics would help but I would guess that is the coolant temp sensor/ sending unit.:pics:

It is I believe 1 of 3 different temp sending units. That one I think if for the computer.

I know its not the main computer sensor. The gauge and comp sensor are in the manidold. The one on top of our tstat has had the wire broke off for 7 years

The wire that is located on the forward p/s of the engine closest to center is the coolant temp sensor for the ecu. Next to it is the cold start injector sensor. Near cyl #3 on the p/s of the valve cover in the head is the guage sending unit. I am not sure what the one on top of the thermostat housing is used for nor can I find any wiring on it. Is it a thermo switch that is only used on automatic transmissions. The 85 4x4 is a FI 5 speed?

David