Originally Posted by paul21
The temperature gauge is hardly a gauge at all. It's programmed to show actual below ~160F? (not sure the exact number but it's not the actual normal temp) and then it just sits in the middle all the time after that. It won't go above until the actual temp crosses a threshold value.
My 99 explorer had an oil pressure "gauge" that was operated off a simple switch. It was either 0 or 50%.
The gauge never shows the actual temperature. It sticks at cold for a while then jumps to somewhere below the middle, then sticks to the middle unless its over heating. By that point it might be too late. However at that point it might be too late.
The car knows what the actual temperature of the coolant is, but the gauge is just for show. If you were to play with the test mode you can watch the actual temperature reading from the coolant temperature sensor.