lexus-is2

When the temperature gauge is in the usual middle halfway mark that it stays at once engine is warm, does anyone know what range of temperature °F values equal to middle place on the gauge? I was reading values on techstream and I was getting readings from 160 to 198 all when gauge is in the middle. Just wondering at what point does the gauge climb higher than the middle. I'm assuming there is probably a optimal temperature range that is defined as the mid point on the gauge? This is just me playing with techstream and trying to understand things better on the car 😀

2013FSport

iTrader: (2)

If it wondered all over reflecting actual temps, people would freak so they normalized it.

At 120°F it is to the left of cold.
At 170°F it is down around 630.
From 178 to 225° it settles at the nearly straight down position.

Remember it can go above boiling as it has 16lb radiator cap and fluid that reduce the boiling point. With glycol it's roughly 225° and under pressure the BP rises to 245 - 250°. That said the gauge tracks over at roughly 225 while the fan(s) come on at 208° or somewhere around there.

Jeff Lange

iTrader: (1)

Basically what 2013FSport said. You basically know if the engine is below operating temperature, within operating temperature, or overheating.

My Yaris has a blue/red indicator that is off within operating temperature and it gives as much information as the gauge on the IS. I remember some older cars that had actual temperature gauges, and people would get quite concerned over the completely normal changes in engine temperature.

To answer your question, the "normal" operating range for the gauge is approximately 80 to 100°C (176 to 212°F).

Jeff

lexus-is2

Great info thanks