Hi!

I'm just genuinely curious. I have a 2008 Honda Civic with the 1.8L engine but this applies to all cars and all engines.

I'm just curious in general how well do cars these days maintain their temp at idle in various conditions?

For example, say I start a car engine on a chilly day with temps in the 40s. I let the car idle for an hour. The coolant temp will have reached operating temp by then I imagine, but just sitting at idle will the temp constantly stay fully warmed up once it's been reached just from being at idle, indefinitely until the engine is shut down?

I know on a freezing day it will take much longer at idle to get hot, but will it eventually get there and properly heat soak?

Likewise, on a hot day or even a below freezing day, how likely is it to maintain proper temp from just starting at idle and running for a period of an hour or two at idle speed? Will the engine "heat soak" properly and stay fully warm even on a windy chilly day at idle? Say if you're using the car to charge a battery or staying warm on a chilly day using the car's heat and need it to idle for a long period.

I don't actually do this, but I'm just curious how well the temp is regulated across many engine sizes etc. across the industry :)