I've got a question about temperature gauge operation. I've always owned
Japanese cars and noticed that once the engine reaches operating temperature
the temperature gauge never moves in the slightest. Yet I can feel hotter
air blowing out of the heater when going up a hill and cooler air when going
down so I'm sure the engine's actual temperature varies. I know the gauge
works since the engine did over-heat once and the gauge slowly climbed into
the red zone as I'd expect. My wife's car is a Saturn and other family
members own Dodges and Fords all of which have temperature gauges that
fluctuate constantly with varying operating conditions.
What is it about the gauges that is different and is there any reason why
one manufacturer would choose one over the other?