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

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

#191

Post by alkonaut »

genewitch wrote: post #67
alkonaut wrote: post #59

First the heater without the engine started for 10-15 minutes, then if it’s really cold I remote start the engine for 5 minutes before driving. But I avoid idling the car cold without running the heater first.

I can only guess that your vehicle has an electric cabin heater that works if the motor is not on? If i "ran the heater without the engine on" in any of my vehicles it would just blow cold air, and for sure one uses engine waste heat for cabin heat.

I use either an electric engine/cabin heater or a fuel burning heater. Of course you need to get the heat from something before the engine is started. Because the engine is what I want to heat before starting it.

On my current car it’s the latter (fuel heater). Often comes with the cold weather package package on new cars at least European ones. Those packs usually add some of heated steering wheel, heated rear seats, fuel engine/cabin heater, retractable headlight washers etc.

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

#192

Post by FooBarWidget »

brookside wrote: post #109
FooBarWidget wrote: post #95

Earlier quoted context omitted.

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…

Are you aware not using the heater does not affect fuel efficiency in an ICE car? Heaters in ICE cars take the pull existing heat from the engine. (I'm not aware of how your hybrid is programmed, it may or may not turn the engine on sooner if the heat is on.) Letting off the gas 100 meters before a stop light and coast that will save gas, but of course it won't be more efficient to brake for the 100 meters before a s…

Turning on the heater reduces my electric miles by a factor of 3. More energy is spent on heating than on moving.

> I think it's worth it to fight the feelings of superiority you allude to in your last sentence.

In every other thread about climate, people hyperventilate about the doom of climate change. But when I try to do my part, it's "100% pointless" and is characterized as merely wanting to feel superior?

This to me sounds like people want to be cynical while at the same time not wanting to do anything about it.

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

#193

Post by P5fRxh5kUvp2th »

Brian_K_White wrote: post #47

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 thought it was just me because I'm not an expert on engines, but apparently not.

And I agree with your last point, it was the other thing that was bothering me by it. What exactly is actionable here, to me it's just normal wear and tear.

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

#194

Post by sokoloff »

BenjiWiebe wrote: post #182
sokoloff wrote: post #148

Earlier quoted context omitted.

My experience is that the viscosity modifiers are more warm-thickening than cold-thinning modifiers. It seems to behave like a low-viscosity base oil and additives to reduce thinning with temperature. (Not a petro /materials engineer.)

I agree with you, but that's essentially cold-thinning when it lets you run an otherwise-too-thin base oil.

Yes. This sub-thread was about “what happens when the additive package wears out; does the oil become full-time thicker or thinner than desired?”

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

#195

Post by falcolas »

BenjiWiebe wrote: post #184
falcolas wrote: post #54

My two cents on this, based on personal observation of driving habits: The real problem is that people will warm up the engine and cab, and then drive the vehicle like the entire thing has warmed up. Something that couldn't be further from the truth. Your tires will be low on air pressure. The entire driveshaft will be dry and its lube will be more viscous than normal. The digital traction controls and diff locks cou…

You are usually supposed to set your tire pressure when cold (and adjust it seasonally) so that shouldn't be an issue.

Nope. Don’t fill them up to spec while cold, otherwise when driving they will be overinflated - possibly dangerously so.

As you run on cold tires, they heat back up, and the tire pressure comes up accordingly. At moderately cold temperatures (20 or so), that can be about 10-15%. At -20 or so, it’s almost 25-30%. Potential blowout territory depending on your tires condition and age.

In more extreme cases, the tires may look dead flat while cold, and perfectly normal once warmed back up.

The volume of air in the tires hasn’t changed, just it’s temperature. And they’re easy to get back up to temp with some easy driving for a few miles.

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

#196

Post by lazide »

pdonis wrote: post #169
lazide wrote: post #128

Earlier quoted context omitted.

The cylinder has rings to remove that oil, hence my comment. There should also be very little to no gasoline contacting the cylinder walls at the bottom of the stroke, or at all. The air currents inside rarely directly contact the cylinder walls. If you have any evidence that the effect you’re describing exists, it would be nice if you link to it!

I don't have any evidence either way, I'm simply trying to get clear about the effect the article is claiming. I am not saying I agree with the article's claims. As I have already said, I don't think the claimed effect would be significant if it exists.

I’m guessing this is the real danger from all the chatgpt like seo crud being generated - lots of ‘maybe, maybe not’ junk generated everywhere that wastes everyone’s time and drowns out useful signal. :(

Eventually, what will we be left with? Authority based credibility? Age based? If it isn’t in a 50 year old book directly available via the library of Congress it’s spam?

Ugh

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

#197

Post by joecool1029 »

UncleEntity wrote: post #114
Glawen wrote: post #90

Earlier quoted context omitted.

Engine oil gets a lot of cargo cult on automotive forums. Personally, I never saw an engine die because it missed the schedule by some thousands km. I wait until my car tells me it needs an oil change, and then I wait a bit more :).

The manufacturers say change the oil every 3000 miles (or whatever), the oil commercials say it is good up to 100,000 miles, split the difference is what I say. My last vehicle did have a bit of a valve train knock though…

Modern synthetic oils can be run for longer intervals with regular filter changes in most vehicles. The 100k claims are on very specific circumstances by a few manufacturers.

The valve hydraulic lifter noise can usually be shut up by using a high detergent oil (I use Rotella t6 in vehicles that do it).

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

#199

Post by pvaldes »

nomel wrote: post #121
pvaldes wrote: post #64

If your oil is too thick to spread accurately, the problem is that you are using an incorrect oil, not that your motor is cold. Oil --must-- work even when is cold. If your area reaches -40F in winter you will need a "0 Winter 30" oil grade; or 0W/30, that is more expensive but very thin so it will not freeze 5W/30 will work until -31F 10W/40 will not freeze until 0F. This is the standard grade used for both winter a…

> Oil --must-- work even when is cold. “Must work when cold” is not the same as “must work at load when cold”. Most modern cars have a limited redline, until the engine warms, because of this.

Non totally optimum performance is not really a problem. The real problem is that USA is huge and cover many different climates. If you drove a car from Florida to NY without taking this in mind, in theory you could end with a non working car stuck in the middle of a dangerous blizzard

I think that there is even a -5W grade for people in really extreme climates like Canada, Russia or Alaska, but I never had seen it. Maybe somebody here uses it?

The last number in oil grades will be 20, 30 or 40 typically for cars. 20 will lubricate pieces faster.

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

#200

Post by jonwest »

givemeethekeys wrote: post #185
jonwest wrote: post #175

Earlier quoted context omitted.

Yeah, from my understanding, basically try to keep the engine load light until at least you’ve warmed your coolant to operating temperature, but ideally 5-10 minutes beyond that as your oil(s) will take longer to heat as they’re more viscous than coolant. Basically, drive like a grandma for ~10-20 minutes before even moderately giving it the business. The flip side of this is that, especially if you’ve got direct por…

Thats asking for a lot, considering my entire commute is 10 minutes, but I hit the highway 1 minute in.

Honestly, the other commenter hit the nail on the head in that "optimum" doesn't mean "necessary"—but 10 minutes of a commute isn't enough to get your engine fully up to working temperature and you are shortening its lifespan. Maybe it doesn't matter to you, and that's totally fine. If you're changing vehicles every couple of years you're probably not even going to run into needing significant repairs as a result of it, but if you're planning on keeping your vehicles for a longer period of time it's definitely something you should consider.
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