I never knew this

[LennG]

So what have you learned recently that you never knew before?

Today I learned this

warming up your car before driving in cold weather can damage the engine

https://www.msn.com/en-us/autos/news/yes-warming-up-your-car-before-driving-in-cold-weather-can-damage-the-engine/ar-AA15xAnV?ocid=msedgntp&cvid=5022ad17a0034490b0a773ce4c220058

"If you're one of the many drivers who thinks it's important to turn on your car and let it sit for a bit before hitting the road in wintry weather, you could be doing your engine more harm than good," Firestone says.
Less oil means more friction, more wear and tear, and a shorter life for your engine," Firestone says.

Instead of waiting for your car to warm up in the winter, most manufacturers recommend driving off gently after about 30 seconds because the engine warms up faster when the car is being driven, according to the U.S. Department of Energy.

[T200]

I'm not completely clueless when it comes to engines but this does not seem correct to me. Specifically, once a car is started, doesn't the engine run (combustion, pistons, oil pump, etc) despite not engaging the transmission?

[MightyGiants]

I'm not completely clueless when it comes to engines but this does not seem correct to me. Specifically, once a car is started, doesn't the engine run (combustion, pistons, oil pump, etc) despite not engaging the transmission?

Tim,

I have a degree in mechanical engineering and even took a class in advanced engine concepts that was taught by a Volvo Engineer (my all-time favorite college class).   

My credentials don't match the guy who was the source of the point raised (the guy has a PHD and works with engines)

However, his point is a valid one.   When engines are cold, they are required to run rich, and that means there is some not vaporized fuel (fuel struggles to vaporize in cold conditions) that, in theory, could get on the cylinder walls and could potentially wash away some oil.


That said, I think it's worth considering:


1)  the damage is to the piston rings and cylinder liners-  these are not parts that you often see fail unless the car is very old with high mileage

2)  the alternative-  while the engine will warm up quicker by gently driving it, the RPMs increase, which means the number of times the cylinder will receive gas at less-than-ideal temperatures doesn't really change, rather it just happens quicker.  Now quicker might reduce the "cleaning" effect of the gas, but I am not so sure


So it is true, you don't need to warm up your car by idling when it's cold.  I would suggest following their suggestion of driving off gently.   On the other hand, if you need to idle it to defrost ice and snow, I would continue to do so because I believe the harm is likely negligible at best.




https://www.businessinsider.com/heres-what-idling-your-car-in-the-morning-is-doing-to-your-engine-and-its-not-good-2016-1

[Ed Vette]

That automatic engine cut off now makes sense.

"f you are idle for more than 30 seconds — such as, at a stop light or train tracks — it may make sense to turn off the ignition. You will use less gasoline restarting the car than when idling, which is why manufacturers have installed automatic stop/start technology on a number of vehicles.'

https://www.carfax.com/blog/do-you-need-to-warm-your-car-up

[MightyGiants]

Thanks to @LennG

I love learning about new things 

[Jolly Blue Giant]

I admit I did not know that Lenny. As for motorcycles (especially Harleys) we are advised to start the bike and let it run for a minute or two before taking off. Unlike modern car engines, the oil in a bike needs to heat up and get distributed through build up of pressure (I guess). If you take off cold on a Harley, you run the risk of no oil in the cylinders for the first mile or so. But...I could also be wrong. It's what every Harley rider has told me over the years, including their mechanics

BTW, I always let my car run to warm up on cold days. Probably should stop doing that....brrrrrrr 

[LennG]

 I think most of us do that so we can get into a car that has some warmth in it. Especially those leather seats where, when ice cold, you just slide right off.

[Ed Vette]

If you lease, it's not an issue. The warranty would cover it and it would take many years for the damage to occur.

[MightyGiants]

If you lease, it's not an issue. The warranty would cover it and it would take many years for the damage to occur.

I am 99.99999% certain that any damage (assuming the claims are correct) would not manifest itself during the timeline and mileage of any lease I am aware of. 

[Sem]

Another variable. Our son in Minnesota relies on an engine block heater and a remote starter. I'm guessing that keeping things warmer and the oil more viscous would be better for your engine. Of course he would still need to clean the glass of ice and snow prior to driving off though.

[LennG]

So let's try another

Ever hear the term "Percussive maintenance"?

It is the act of hitting something until you can get it to work

https://theriver973.iheart.com/featured/glenn/content/2017-10-05-fact-this-is-the-technical-term-for-hitting-something-until-it-works/


And another term    The primacy effect

Here's the basic idea of the primacy effect: when presented with a list of information, you are most likely to recall items at the beginning of the list. These items are more likely to end up in your long-term memory than items at the middle or the end of the list.

https://practicalpie.com/primacy-effect-examples/#:~:text=Here%E2%80%99s%20the%20basic%20idea%20of%20the%20primacy%20effect%3A,the%20middle%20or%20the%20end%20of%20the%20list.

[MightyGiants]

So let's try another

Ever hear the term "Percussive maintenance"?

It is the act of hitting something until you can get it to work

https://theriver973.iheart.com/featured/glenn/content/2017-10-05-fact-this-is-the-technical-term-for-hitting-something-until-it-works/

We used to call that impact motivation 

[Sem]

"So let's try another
Ever hear the term "Percussive maintenance"?
It is the act of hitting something until you can get it to work"

Len, I hope you're not talking about your wife!!!