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What temp should an engine run at?

How do you know if your engine is operating at its correct temp? I know my temp gauge is always around the same mark and about how long it takes to get at that mark, but how do I know it’s not running to hot or to cool at that mark?

The manufacturer determines the proper operating temperature and chooses a thermostat that maintains that temperature, at least within an acceptable range. The gauge is also chosen to simply show when everything is normal (or when it isn’t).

As long as your gauge shows its familiar reading, you can be assured that all is well.

Older cars ran at 180 degrees, while modern pressurized systems with the new year round coolant tend to run at 212F, which would be the boiling point of water if that’s all you had in the rad.

As per the previous post, normally your gauge has no numbers, they just confuse drivers, but an operating range; and if the gauge is about halfway up that’s your normal operating temperature.

Any major deviation from that is cause for concern and should be investigated.

My car is a 98 ford, my temp gauge goes about half way when I first start the car in the morning or after it has sat for many hours. Once there it will drop down and be maybe a little under that. So I guess my engine temp is where it should be. Why don’t they list like 100-200-300 and such and that way you would have a better grasp.

Change the thermostat every 4-5 years and it’ll be fine.

As long as it’s in the middle (and everything’s working fine) you’re OK. A number of ‘gauges’ are now fancy-looking idiot lights, with no real quantitative meaning to the needle position. It’s either low for ‘cold’, middle for ‘ok’, or high for ‘too hot’.

It depends on the ambient air temperature and whether or not the AC is being used. Once the thermostat opens the engine coolant temperature can run from 210-230 degrees.

Tester

Engines are made to run a little warmer now than in the past due to emission control requirements. As far as you need be concerned, if the Check Engine Light does not show, the car does not overheat as indicated by the temperature gauge or steam from under the hood and if the heater produces enough heat then you need not be concerned. Engine temperature is important but not critical.

Our newer car with a digital temperature gauge readout runs about 190F.

To really know if an engine is, or is not, running too hot, or too cool, is to use an accurate thermometer. How smoothly an emgine runs can INDICATE (but, not prove) that it is (or, not) running at the correct temperature.
The normal operating temperature of the coolant in an engine is about 210F to 240F degrees. The thermostat OPENS at 195F degrees; but, the temperature continues to rise to the normal operating temperature. The temperature of the coolant can rise above 212F degrees because coolant is pressurized (NOT because the water is mixed with antifreeze). Boil-over won’t occur until about 265F degrees, because of the pressurization (15 or 16 psi).

Generally, between 175 and 240 degrees F, depending on whether you are going downhill or uphill. If you are going up the hill from Camarillo to Thousand Oaks, maybe higher than 240.

Why don’t they list like 100-200-300 and such and that way you would have a better grasp.

It would likely confuse more people than it would help. What they are trying to do is to let you know it is OK or that there is a problem. You are doing fine.

The temperature of the coolant can rise above 212F degrees because
coolant is pressurized (NOT because the water is mixed with antifreeze).

The coolant being under pressure definitely raises the boiling point per well defined forumlas. But I’m curious why you feel the antifreeze doesn’t contribute to some of the increase as well.

BTW, if it is not getting warm enough, the CEL will illuminate.