Pickup 4WD L4-2366cc 2.4L SOHC (22R) (1984)
Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection
Drain coolant and remove thermo switch.
Cool thermo switch to below 109°F and check that switch has continuity.
Heat switch to above 131°F and check that there is no continuity.
Apply liquid sealer to threads of switch and reinstall it, then refill radiator with coolant.