I have a 92' Ford Ranger with 2.9 V6. As long as I can remember, the radiator fan runs 100% of the time when engine is running, regardless of hold or cold weather. A mechanic said the fan should only run when it is hot

Is this correct for my make and model? I guess this what fan clutch if for?

Thanks,
Dave

 

The fan should kick on when the sensor reaches a certain temp and turns it on. Must be the fan sensor.

 

I also suspect that it is a sensor issue. To ensure that the fan will spin at the proper speed (preventing the engine from overheating) as well as to decrease drive to the fan when it is no longer needed is basically what your fan clutch does.