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Warming up your car before driving in cold weather can damage the engine (2016)

businessinsider.com

131–140 of 200 posts

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#131

I don't doubt that the expert consulted for this article knows way more about gasoline engines than I do, but the article itself contains some flat-out falsehoods. In particular the line "But don't confuse warm air coming from your car's radiator with a warm engine." is just wrong. The engine temperature sensor actually senses the engine coolant temperature, and if your dash is blowing warm air, then the coolant is w…

Many new cars have electric heaters for the air venting into the cabin. In that case their statement about confusing warm air with a warm engine would be true.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#132

Earlier quoted context omitted.

Oil pressure seems to be left out of the conversation - oil-starved journal bearings can be bad news if loaded immediately. SOP in piston-engine aircraft is to get the oil temperature and pressure "in the green" before doing run-ups. There's a pretty good description here: https://www.machinerylubrication.com/Read/779/journal-bearin...

Piston Engine aircraft are probably not the right example to use. They are almost exclusively air/oil-cooled, low-rpm engines, and a majority of them have designs dating back 50+ years.

sure, but the basic physics at the very heart of the issue (use oil to avoid direct contact between metal pieces) is exactly the same.

it seems very unlikely that modern refinements have completely reversed the concerns.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#133

I'm sure the cited expert really is an expert, but this article fails miserably at conveying any cohesive understanding from them to you. It's full of conclusions that don't follow from their leading statements. My understanding about warming up an engine before putting load on it had nothing to do with fuel or power steering fluid, it was about thermal expansion of all the machined parts that suffer wear if they are…

I have the same recommendation on my car user manual, don't warm the engine, but take off after start up and take it slow for a few minutes until the engine water moves off the base. I know one of the engineers that worked at the car design and when questioned, he explained (going off memory here) that people used to warm the engine, then started driving normally, and while the engine is hot, the trasmission and diff…

Thank you. This makes sense.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#134

For me the benefits far outweigh the increased wear on the engine. I don't really need my engine to last 400k miles like it can in perfect circumstances. I need fog free windows, be comfortable driving the car without gloves on making the steering slip. To be able to focus on getting around and not shivering. I don't drive these days but back when I did those were all issues I had for my 5am start getting to work. An…

Interesting that you think about it that way. My primary goals are the opposite: 1. To save as much money as possible. Meaning to make my car last as long as possible, postponing the need for repairs or a new car as long as possible 2. To reduce energy usage as much as possible. Not only to save money but also because it's good for the environment. Which means I do exactly the opposite of yours. I'll to go great leng…

I used to be the same way too but in warmer weather I would try not to run the A/C in my car. I think that kind of turned out to be a bad decision though because my car was older and by refusing to turn on the A/C, I think that might have made it more likely for the system to get messed up. I don't know the exact reasons, but maybe it has to do with the lack of pressure and the coolant not circulating.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#135
Many modern vehicles (particularly light diesels) are so fuel-efficient that they won't warm up no matter how long you leave them idling.

I needed to fit an old-fashioned radiator blind to the Mercedes van I used at work, because in the winter the engine would not reach operating temperature in a 15-mile drive from my house to my workshop.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#136

I'm sure the cited expert really is an expert, but this article fails miserably at conveying any cohesive understanding from them to you. It's full of conclusions that don't follow from their leading statements. My understanding about warming up an engine before putting load on it had nothing to do with fuel or power steering fluid, it was about thermal expansion of all the machined parts that suffer wear if they are…

Oil pressure seems to be left out of the conversation - oil-starved journal bearings can be bad news if loaded immediately. SOP in piston-engine aircraft is to get the oil temperature and pressure "in the green" before doing run-ups. There's a pretty good description here: https://www.machinerylubrication.com/Read/779/journal-bearin...

If your engine doesn't have oil pressure before it's even finished starting, either it's a bit faulty or you're using a grossly incorrect grade of oil.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#137
post #73

Earlier quoted context omitted.

I am the guy that preheats his Honda to perfection. I will fly like a bat out of hell out of my front door in my boxers to start the car and run back inside to get ready for another 30 minutes. Yes, I am a total badass. I’m not worried about maintenance because that is a fact of life. For Tesla’s too (mostly defects). If your car breaks down shortly after you start driving it and the cabin is ice cold you’re in troub…

This is a real important point - many drivers in the cold aren’t dressed for it at all and though even many rural roads will have someone pass by relatively soon a warm car is going to be nicer. Of course anyone driving in freezing areas should have winter survival gear but who actually does?

Since having kids, always. I’m not particularly fussed about my comfort, but I really don’t want to have to walk a couple miles carrying an underdressed two-year-old (or leave them in the car).

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#138

Earlier quoted context omitted.

Anecdotally, my transmission doesn't shift as well if I drive it right away in the cold.

Yea on cold mornings I have to skip 2nd gear and go straight to 3rd, since I can't get into 2nd gear the first few times.

You should change your gearbox oil.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#139

I claim no expertise, as this is the internet and my credentials are entirely virtual and imaginary. * Business insider is often a click bait. * Taxis and Police cars idle all day. That's fine because their engine is warm. We're talking about damage being done at cold start and idle. * The only time the engine is without much lubricant is when it is cranked. * When the engine has started and running, oil is forced in…

Idling all day comes with its own issues too.

Re: Warming up your car before driving in cold weather can damage the engine (2016)

#140

The title needs clarification that this is for ICE cars... That is those with internal combustion engines. 10-15 years from now this kind of article is going to be somewhat anachronistic sounding.

I think you're very optimistic, IMO the timeline is 30-50 years.
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