Thermostat thread

[dr. d]

No, he means that the temp gauge stays at the same place even if the engine temp varies within its nominal operating temp. It's non-linear.

For most vehicles, the temp gauge stays put in its "normal operating temp" position if the actual coolant temp is between 85°C to 110°C or whereabouts. They made it such so that the driver doesn't panic when the non-graduated temp gauge starts swinging up and down during the course of the trip.

Depending on the vehicle, the temp gauge would only start creeping into the Hot range when the coolant temp gets past the operating temp threshold set inside the ECM. My guess would be 115-120°C onward. At this point, the gauge moves at an exponential rate.

i also read his post (#1).
upon reading and re-reading it several times, he probably meant that the temp gauge didn't budge from its overnight cold reading, even as the engine is already noticeably warmer to the touch.

if i may, that is probably true of most cars that still have needle gauges.
my own car's gauge moves up a notch, only after about 1 km.
(but i don't stop to open the hood and feel the engine, to see just how warm it is.)