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Comment by hristov | Hacker News Reader

With an ICE car, if you park regularly in very cold weather, your car can fail randomly for an obscure reason and it can take a long time to figure it out or you will need a trip to the mechanic. Or you may need a massive and expensive repair.

Remember that a lot of people have to spend 10-15 minutes warming up their cars before they drive them in cold weather.

I do not want to go into details, better car mechanics than me should, but there is all kind of chaos that can happen if your engine freezes and you try to drive it immediately. And it is much more complex and can be much more expensive. Once you start getting cracks in various things and liquids flowing where they should not be you will wish for the simplicity of just plugging in your EV.

So lets not pretend that driving in the cold is some kind of new problem that EVs introduced.

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> Remember that a lot of people have to spend 10-15 minutes warming up their cars before they drive them in cold weather.

People choose to do this. This isn’t required and it’s recommended against in modern vehicles.

> I do not want to go into details, better car mechanics than me should, but there is all kind of chaos that can happen if your engine freezes and you try to drive it immediately.

Engines do not freeze in the conditions common in most of the US, even with winter like we’re currently having. The engine coolant is a mixture of anti-freeze and water.

> People choose to do this. This isn’t required and it’s recommended against in modern vehicles.

I’m curious about that recommendation, do you know why that is?

Because it’s much more efficient to heat up a modern car by driving it than it is to let it idle.

You need N joules to heat up the 300kg of the engine. It doesn't matter if you sit there for 15 minutes freezing your ass with an engine running at 1500rpm (and all other car parts still freezing) or 5 minutes actually driving at 3000rpm - you still spent N joules on heating, difference is the time. And the car heater runs on the engine heat, not on the electricity, so the sooner you would warm the engine the sooner your car interior start to warm and stops seeping the heat from engine.

It's actually more importantly to have enough viscosity in ATF, but again, the sooner you would go the sooner it would warm.

It's possible you need to idle for 10 minutes just to scrape the ice off your windows though :)

You don’t need to idle the car for 10 minutes to scrape the ice off. You can scrape it off with the engine off.

For the good of the engine maybe. For the good of the driver... when you're finished scraping off it's better inside. Plus the windows kinda warmed up so it's easier to scrape.

Not sure what is the assumption. I have the opportunity to scrape the ice off of the car many times a year.

Depends on the weather. There were a multiple times when the running engine heating up the windshield was the necessary prerequisite to scrape the ice off.

Its just that I care more about my comfort than wear on the engine

I've definitely had a serious enough layer of ice on the windshield that my nice scraper was an exercise in futility. Maybe 2-3 times a year, but it's a thing.

> I’m curious about that recommendation, do you know why that is?

I was always told (since the 90s, anyway) that it's better to drive off slowly with a cold engine and let all the components come up to operating temperature together than to drive off with a hot engine, and cold gearbox, driveshafts, tyres, etc.

I generally let a cold engine (i.e. overnight) idle for maybe 30s before driving off slowly, and it reaches operating temperature in about 5m or less.

Because your car engine does not get the right mixture until you start driving.

In a 2022 car I have now even the cabin doesn’t get proper heating from the aircon until it’s driven.

> your car can fail randomly for an obscure reason

Your electric car can fail randomly for an obscure reason too, and good luck getting anyone at all that can fix it.

> Remember that a lot of people have to spend 10-15 minutes warming up their cars before they drive them in cold weather.

Only because they're idiots. No-one needs to leave a vehicle for 10 minutes to "warm up", even in the coldest of weather. Drive gently until the temperature gauge is a bit off the end stop, and then drive a bit less gently until it's at its proper operating temperature.

Alternatively, start the engine from stone cold and immediately drive off at full throttle taking it up to 70mph before there's even a sniff of warm air from the heater. This is *still* better for it than letting it sit for a long time to "warm up".

> Only because they're idiots.

Even if we ignore the "heard bad advice" versus "idiot" issue, that's still untrue because there are other reasons besides what's best for the machine.

Maybe they aren't in the car, and they're warming it up to be comfortable.

Maybe there is ice on the car they need to melt.

Use deicing spray to get the ice off the car. If it's too cold for you in the car, then just sack up and get on with it. You're not going to come to any harm being a wee bit cold for a couple of minutes, and the heater will actually start working quicker if you drive. If the weather is as cold as it gets here in Scotland in winter, the car will *never* warm up sitting idling.

So I'm an idiot if I avoid things that are unpleasant but won't harm me? And again, speed doesn't matter if I'm not in the car.

Or I'm an idiot if I would rather idle than pour alcohol on my windshield?

> If the weather is as cold as it gets here in Scotland in winter, the car will never warm up sitting idling.

Okay, then that person is an idiot, but it doesn't extend to the people actually warming up their car.

'all kind of chaos that can happen if your engine freezes and you try to drive it immediately.' the coolant in ICE vehicles is called antifreeze, only an idiot would substitute H20 for that in cold weather, or any other time for that matter as it is designed to help protect the interior of the engine.

That are only problems when you live in russia or maybee canada.

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