??? coolant sensors

Can anyone tell what the difference is is between the coolant sensors in any dodge or chrysler products as it seems they all have the same purpose but different part numbers? I have tested them all from 25 different chryco products and engine classes with no difference in readings or voltages as well as ohms. I have switched the sensors from various vehicles and there seems to be no difference in the operation of the engine or fuel economy, with the exception of the faulty sensors that I have tried. Does anyone have a view on this topic?

on some older engines, they had a coolant temp gauge wire and a coolant temp sensor that worked to feed information with the engine computer. I'm guessing you are referring to the coolant temp sensor controlled by the engine. That sensor is a thermistor, meaning as the temp. is lower, the resistance is higher and when the temp is higher, the resistance is lower. As far as there being any difference, there really isn't, as long as it performs its basic function, it's doing it's job.