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Comment by delecti | Hacker News Reader

I have. Driving the car causes so much more heat production by the engine than idling that it barely makes a difference.

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The difference is that the heat is going the moment I get in my car. Not as efficient (and, to be fair, my experience is a bit dated here [~15 years]), but I don't have to freeze my butt off for 10 mins waiting.

This is ridiculous, I have never had a car need ten minutes of driving to make heat, even in a Pittsburgh winter. I have had a driving license for 36 years.

I drove a Renault Zoe around Stockholm in the middle of winter. Great car, except for the heating... takes a long time for it's little heat pump to warm up.

Is that an all electric car? Petrol combustion gives off a lot of heat, but if the thermostat is stuck open this works against the goal - modern vehicles will set a fault in this case because slow warm up causes more fuel to be burned and emissions to be expelled.

Yes the Zoe is all electric.

The difference is that your pistons, rings, bearings, etc have not come up to operating temperature and have not expanded due to heat. It's not going to explode immediately but you are reducing the overall lifespan of the moving parts if you drive on a cold engine.

Most modern cars are a lot more tolerant thanks to advancements in oil technology. But it is to a greater or lesser extent better to warm your car up, even if it's not immediately / apparently necessary to you.

You're not supposed to floor it and giver 6.5 when she's cold. Driving with low loads and low RPMs will bring it quickly up to temperature and produce minimal wear; I've been told it actually produces less wear as the engine runs less time/revs cold.

It's a different story if you're pulling a heavy load and can't do anything about it. Then letting her warm up makes some sense. Most people don't do that.

Yeah thats right. I build race engines as a hobby (currently have a cp-carrillo mazda BP in the works) and (I like to think) I have an understanding of mechanical sympathy. Obviously performance engines have different tolerances to mass-produced consumer items, but I like to treat them the same.

The benefits to slow driving is that it also brings the drivetrain up to operating temps as well - it's no good if the engine's at a good oil temperature but the differential and gearbox is still icy. But even letting the car idle for 10-20 seconds so it can push oil around the block, fill the galleries and start filling the lifters/head will help extend the lifespan of an engine, and then combined with a slow initial drive to allow everything to come up to temperature you should be able to give the car a bit more life.

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