Corollas2019-23ToyotasTech

Search Corolland!

Is A Steady Temp Reading Normal?

by TomGibson, February 25, 2015



I have a 2000 Corolla, and I've always thought it was normal for the temperature dial to slowly to rise to just under halfway, then hold there until the engine is turned off. I recently drove a friend's car and notice that the temperature dial in that car would actually change depending on what the car was doing. For example it actually rose while on the freeway, then lowered again after getting off the freeway. Mine gauge stays steady no matter what I'm doing or how I'm driving. Do I just have a good cooling system? Or is my gauge or sensor possibly broken? How would I check?

Nope - yours is doing exactly what it should be doing. Cooling system will rise in temperature until it hits the operating temp, then it does all it can to maintain that temperature for efficient operation.

Temperature shouldn't jump around due to engine load - that is a likely a sign of a possible bad temperature sending unit or worse a fault in the cooling system.

If you are really curious on what is happening, you can plumb in a higher resolution temperature gauge. In the mean time - I wouldn't worry about it. Mine acts just like yours - rises up to the 1/2 way point and stays there until I shut the engine off.

My 2004's temperature gauge reading is very stable as well... Some older or poorly engineered models like my sister's 2003 Buick Regal 3.8 V6 is nowhere near as stable, and is harder to maintain an acceptable operating temperature during very cold winters. It also typically rises on highway. My old mechanics instructor used to say the hotter running temperature at higher speeds is to be expected and is also desirable to decrease engine wear.

A stable and well managed engine operating temperature is in fact crucial for optimum efficiency and dependability... Your friend's car's cooling system may need some attention. Could be a faulty thermostat, or low coolant level, or other.



Topic List