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Warming up your car before driving in cold weather can damage the engine (2016)
- bitxbitxbitcoin 4y agoBut what about for a Diesel engine?
- rolph 4y agoyes thats a big hole in the article. diesel is oil, its a wet fuel, like gasoline [vs propane]. diesels here in AK usually run with winter additive or ether start. the best bet really is block heater, its built in most vehicles here, but there are "stick on hot pads" you can put on your oilpan. these are high heat, you can cook an egg on one if you wait a little longer
- lazide 4y agoWithout winter mix, diesel also congeals at low temps. Then you’re in deep trouble haha.
- smitty1e 4y agoMy little TDI needs some serious amps compared to a tegular gas engine.
- LadyCailin 4y agoVery little information in this “article”.
- dang 4y agoOk, we've changed the url https://www.fleetmanagementweekly.com/yes-warming-up-your-car-before-driving-in-cold-weather-can-damage-the-engine/ https://www.fleetmanagementweekly.com/yes-warming-up-your-ca... to the thing it points to, which is longer if not better. Edit: ok, that one (https://www.verifythis.com/article/news/verify/weather-verify/warming-up-your-car-in-cold-weather-winter-can-cause-engine-damage-fact-check/536-8bf406d7-194c-4ca0-a06d-d1d56006e5d9 https://www.verifythis.com/article/news/verify/weather-verif...) didn't work. Switching to the URL suggested in the comments below. Thanks!
- aidos 4y agoGetting access denied. Sorry dang, this is not a great way to spend Christmas (thanks for the ceaseless moderation!).
- timmaxw 4y agoFollowing the chain of links, I think this article is the original source: https://www.businessinsider.com/heres-what-idling-your-car-in-the-morning-is-doing-to-your-engine-and-its-not-good-2016-1 https://www.businessinsider.com/heres-what-idling-your-car-i... It's a much more detailed article, including some specific claims about the science.
- semi-extrinsic 4y agoThis, from 2016, seems to be the original post and seems to be fairly well written, if surprising and controversial https://www.businessinsider.com/heres-what-idling-your-car-in-the-morning-is-doing-to-your-engine-and-its-not-good-2016-1 https://www.businessinsider.com/heres-what-idling-your-car-i...
- dang 4y agoOk, we'll try that one - thanks!
- windmark 4y agoI can’t access the updated link and just get: Access Denied You don't have permission to access "http://www.verifythis.com/article/news/verify/weather-verify/warming-up-your-car-in-cold-weather-winter-can-cause-engine-damage-fact-check/536-8bf406d7-194c-4ca0-a06d-d1d56006e5d9 http://www.verifythis.com/article/news/verify/weather-verify..." on this server. Reference #18.51d1202.1671993608.7d094d83
- rolph 4y agohere in alaska we use block heaters as a must have. Cold oil doesnt recirculate very well, of course a chronicaly cold engine, with cold oil, is going to display excessive wear. so, why "warmup" a vehicle? two parts... 1] old model vehicles dont have digital engine control its electromechanical. cold carburetors run out of tune, unless you have auto choke and idle tuning. so the block needs to be warm for efficiency and normal function. 2] it gets cold in the cabin of a alaskan vehicle no matter what make/model, as in deep negatives and hoar frost all over. most humans dont do well in this, and have to warmup the cabin to function outside of hypothermia. this is afew levels beyond scraping frost of a window.
- barbazoo 4y agoI love how the examples are always Alaskan winters but you see people idling their car to warm up everywhere and often in moderate temperatures. For most, it's a comfort thing and not necessary.
- Brian_K_White 4y agoIf you're even using a car at all, then you have already decided that comfort and convenience are necessary.
- barbazoo 4y agoLet's not make the perfect be the enemy of the good.
- Brian_K_White 4y agoI'm not sure how this is supposed to apply. I am asserting that the function of the car is to provide a comfortable environment, not merely to physically transport. Otherwise why does it even have a heater or an air conditioner? I don't think there is any valid argument for austerity on this tooic. I am saying it's perfectly valid to warm the car up simply because you want to because it's more comfortable and makes clearing the windows easier, because the only reason the car even exists is to be a tool to make your life easier. If that warm up time consumes some of the device's life, so what? Every minute of use consumes a minute of it's life. These few minutes of use are no different than any other few minutes of use.
- sschueller 4y ago"peratures can shorten the life of your engine by stripping away oil from the engine’s pistons and cylinders — two critical components that help your engine run." Nonsense, if the oil pump and engine are built correctly and working as intended this does not cause librication not to work correctly. How many cabs would die early because they are idling in traffic all day? Your personal cars engine is not a formula one cars engine that survives one weekend of driving.
- hprotagonist 4y ago> How many cabs would die early because they are idling in traffic all day? and cop cars? Approximately all of them. This is well known. https://old.reddit.com/r/MechanicAdvice/comments/4pjnco/how_does_idling_negatively_effect_police_vehicles https://old.reddit.com/r/MechanicAdvice/comments/4pjnco/how_...
- LinuxBender 4y agoI think these discussions are risky because of causation/correlation. Cabs, police cars, UPS/Fed-Ex trucks need engine/transmission rebuilds sooner because they stop/start every day all day long. For example a Fed-Ex panel truck with a Cummins engine and Allison drive train will last for about 1 million miles without rebuild if used as a light duty such as a plumber or electrician or personal vehicle. Used as a Fed-Ex delivery vehicle it will need a rebuild at around 410K to 450K miles. Idling is not causing the engine to need a rebuild at 40% of it's normal lifespan, its shutting it off and starting it over and over all day long.
- BenjiWiebe 4y agoAnd the way delivery drivers drive... Our UPS guy drives in a way that makes us surprised his vehicle lasts for a week...
- sokoloff 4y agoNote that, for cost reasons, F1 teams are limited to 3 engines per driver for the season, with penalties for starting grid positions for exceeding this figure.
- aidos 4y agoThis feels a bit shallow. According to this website, another website says that warming your car in cold weather before driving can cause damage due to stripping oil from the piston. I’m willing to believe it but I’d like to hear some details. Surely the engine is going to warm to the same temperature soon enough?
- vsri 4y agoYeah, this is confusing. Does this mean idling your car is bad for the engine?
- rolph 4y agonot if the oil is warm. if its cold where you are use a block heater so your oil is warm to begin with. then you can idle no problem, and get the cabin up to a human temperature
- dang 4y agoWe've since changed the URL. I don't know if the current article is still shallow but hopefully it is less annoying.
- michaelteter 4y agoYet another closed access post on HN. My last complaint about this got flagged, but I really don't care. The HN community needs to stand behind open internet, not contribute to an increasingly closed one. "Access Denied You don't have permission to access "http://www.verifythis.com/article/news/verify/weather-verify/warming-up-your-car-in-cold-weather-winter-can-cause-engine-damage-fact-check/536-8bf406d7-194c-4ca0-a06d-d1d56006e5d9 http://www.verifythis.com/article/news/verify/weather-verify..." on this server. Reference #18.6dc31302.1671993353.baa1f4a "
- minusf 4y agoisnt that akamai cdn blocking vpn ips?
- NikkiA 4y agoIt's a flask routing error, iirc.
- aidos 4y agoThat was caused by changing the original url.
- michaelteter 4y agoI merely clicked the link. I am on a VPN at the moment as I am traveling in Asia. Even so, while paywalls are my #1 complaint, US-based sites who stonewall EU visitors is my #2. All they have to do is not collect data and then they don't have to worry about GDPR. Blocking EU visitors is a cop-out, and one that hurts them more. We can probably live without their "news". They're just losing eyes and traffic.
- soared 4y agoWorks fine for me, is that not just a temporary 403 error?
- rahimnathwani 4y agoThe site is free to access. There's no paywall. I was able to reproduce the error you got by accessing it through a browser in the UK. I guess the site blocks access from countries that require compliance with GDPR. I don't think people should be required to test that the site is available in every country, before posting or upvoting.
- psychphysic 4y agoFor 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. And far more a concern to me than the engine losing some longevity (which I could make up for just by proper care few people do anyways).
- godelski 4y ago> I need fog free windows Personally I can't drive with ice on my windows. Can't really see outside and I'm pretty confident that's illegal. Like 80%, but I'm not a lawyer.
- eastbound 4y ago100%: Driver must keep the car in state of driving - or something like that - It includes everything.
- Turing_Machine 4y agoYou will definitely get a ticket here if a cop sees you driving with windows iced or fogged up (which you should... it's a serious hazard to you, other drivers, and pedestrians).
- postalrat 4y agoUnless you have been driving for 2 hours you will probably have some ice on your windows some days here in MN.
- bluGill 4y agoOn most mornings my windows will fog on the side I just cleared before I can get the other side clear. I clean my windows, and then a couple miles down the road they clear up, otherwise it's will be a while before they are clear.
- doubled112 4y ago
- danesparza 4y agoUm. This article is so short it doesn't even have a "logical leap", much less any evidence. Just opinion.
- vsri 4y agoThis URL didn't work for me, but I found this: https://www.verifythis.com/article/news/verify/weather-verify/warming-up-your-car-in-cold-weather-winter-can-cause-engine-damage-fact-check/536-8bf406d7-194c-4ca0-a06d-d1d56006e5d9 https://www.verifythis.com/article/news/verify/weather-verif...
- amluto 4y agoWow. This is unreal. The OP says: > In a blog post on its website, Smart Motors Toyota says letting your car idle in cold temperatures can shorten the life of your engine by stripping away oil from the engine’s pistons and cylinders — two critical components that help your engine run. > via VERIFY Great, they got some kind of content from somewhere else. Let’s follow the link to verifythis.com: > Yes, warming up your car before driving in cold weather can damage the engine. > In a blog post on its website, Smart Motors Toyota says letting your car idle in cold temperatures can shorten the life of your engine by stripping away oil from the engine’s pistons and cylinders There’s even a video! Let’s click the actual link to smarttoyota.com: > Warming up your vehicle can actually shorten the life of your engine, by letting your vehicle idle in the cold you are actually stripping away oil from the engine’s pistons and cylinders each time you do this. While you may wonder where this myth came from since it’s not true, it’s because it was once based on facts. Jake Scheafer the Service Director at Smart Motors’ says before cars and trucks were equipped with fuel management systems, they relied on carburetors and simpler fuel system management which did need significant time to warm up. Hint: next time you make a video based on some other source, try reading at least two sentences. OTOH, the bar seems really low for ChatGPT to emulate the capabilities of these websites…
- dang 4y agoIf someone can suggest the best URL for this topic, we can change it again. (It was even worse before.) Edit: we changed the URL from https://www.verifythis.com/article/news/verify/weather-verify/warming-up-your-car-in-cold-weather-winter-can-cause-engine-damage-fact-check/536-8bf406d7-194c-4ca0-a06d-d1d56006e5d9 https://www.verifythis.com/article/news/verify/weather-verif... now, to the article suggested by timmaxw and semi-extrinsic.
- genewitch 4y agoamazing, the entire premise is false.
- Jordrok 4y agoI think you're misunderstanding. The "myth" being referred to in that third link is that it's beneficial to warm up your engine by letting it idle for a long time. This was previously true for cars with carburetors, but is no longer useful for modern cars. The idea that idling the engine for an extended time after a cold startup can cause damage is correct, and that idea is consistent in all three articles you're referring to.
- EamonnMR 4y agoWhen your engine is running the oil pump ought to be circulating oil across relevant surfaces, I don't see how idling would 'strip it away.' If that was the case, why would they sell cars with remote starters?
- pdonis 4y ago> I don't see how idling would 'strip it away.' What the article is saying here is technically correct, but I doubt the effect is as large or as detrimental as the article says. The key point is that, as the piston moves up and down in the cylinder, the part of the cylinder wall that is traversed is alternately wetted by oil and gasoline. When it is wetted by gasoline (i.e., when the piston is at the bottom of its stroke), some of the oil can dissolve. But when it is wetted by oil again (i.e., when the piston is at the top of its stroke), as you say, the oil pump will push more oil onto the surface and replace what was lost. So the actual effect will be to very slowly decrease the amount of oil in the engine. This might also mean a small increase in engine wear, but I would not expect that to be very significant compared to all the other sources of engine wear. If one is really concerned about the possible loss of oil, just check the level between changes (which many people do anyway).
- lazide 4y agoIf you are getting more than a super tiny film of oil in the cylinder, you’re burning oil because your rings are toast. That has nothing to do with temperature, usually.
- pdonis 4y ago> If you are getting more than a super tiny film of oil in the cylinder, you’re burning oil because your rings are toast. The "cylinder" is more than just the portion where combustion occurs, when the piston is at or near top dead center. The portion the article is talking about is the portion that, as I said in my previous post, is exposed to gasoline when the piston is at the bottom of its stroke--as it will be at the end of both the intake and the power strokes in a 4-stroke engine. If the mixture is rich, there will be extra gasoline present under those conditions that, according to the article, could dissolve the oil wetting the cylinder walls. That will be the case even if the rings are fine. I just don't think it's anywhere near as significant as the article claims, because, as the poster I responded to pointed out, even if some oil is dissolved in the extra gasoline, it will be replaced as the piston rises again and that portion of the cylinder wall is on the oil side of the rings.
- BonoboIO 4y agoThis is just plain wrong. The whole article. What kind of content farm puts those articles out.
- bloodyplonker22 4y agoAlways take Business Insider with a huge grain of salt. In addition, their articles can be very politically biased, if you know what I mean. Always consider the other side of the argument when reading from lower tier sources like Business Insider.
- lazide 4y agoChatGPT?
- gonzo 4y agoThis. Exactly.
- Brian_K_White 4y agoI'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 run under load while they are loose-fitting from being cold. This is a thing even in summer and merely worse in winter. This article barely talks about this and doesn't say anything intelligible but just says "stress" from stepping on it right away. Maybe that issue also no longer exists on modern engines, but nothing in this article explains that. Mostly everything this says about why idling is supposedly bad, applies to operating the thing at all, idling or not. The conclusion would be "don't use your car at all in winter" Well, if you're going to use it at all, then you're already doing the damage, so you might as well be comfortable and have an easier time clearing the windows. The device only exists in the first place to serve you.
- willnonya 4y agoAbsolutely. The risk of putting load on the engine before the moving parts and oil have reached operating temps is far greater than the threat of tiny amounts of gasoline washing residual oil from the cylinder walls or thinning the oil. The only risk described here applies to prolonged idling only and is a long term risk mitigated by reasonable elwarmuo and oil changes. The short term risk is the rotating assembly and value train is far more immediate. Fuel injection has convinced people that they can just jump in a cold car, fire it up and be fine. Doing so, especially in extreme cold is just incredibly damaging.
- nickff 4y agoI work in this industry (designing tools for automotive diagnostics), and have heard many arguments either way WRT warming up engines; I do not understand yours.
- nickff 4y agoI work on the repairs side of this industry (diagnostic tools), and have come to the conclusion that while the thermal expansion is an issue, it’s probably not the largest or most fundamental one. When an engine idles (with no load), it produces relatively little heat. Comparatively, an engine running faster, under load produces much more heat. The engine will warm up more quickly and less evenly when loaded, likely leading to thermal stress, and possible mismatched thermal expansion. On the other hand, modern lubricants are very good at handling different temperatures. The other thing to consider is that the engine is only one part of the vehicle, and various other components of the drivetrain may actually suffer more thermal stress from the idling than from immediate driving.
- falcolas 4y agoMy 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 could be stuck (or at abnormally slow to respond). So, IMO, while there's benefit to letting an engine warm up, keep it under 2k RPM for the first couple of miles; until the entire drive train is also warmed up.
- BenjiWiebe 4y agoYou are usually supposed to set your tire pressure when cold (and adjust it seasonally) so that shouldn't be an issue.
- falcolas 4y agoNope. 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.
- alkonaut 4y agoFirst 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.
- genewitch 4y agoI 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.
- alkonaut 4y agoI 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.
- devwastaken 4y agoOil is more viscous in colder temps, especially at 0f and below. The oil needs to rise from the pan and up into the pistons, the piston seals assume a certain viscosity of oil. You want to have as little stress as possible until the oil reaches even just room temp. While revving the engine up won't immediately destroy it, that heat does not transfer from the pistons to all of the oil simultaneously. Synthetic oils have a wider temp range where they maintain viscosity and lubricating properties. Of anything, always recommend good quality full synthetic oils for cold climates.
- pvaldes 4y agoIf 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 and summer in many temperate areas If you use the 15W grade for tropical areas in cold places, the oil could be too thick, will freeze at night and lose their properties. If you start the car without warming it first, you will probably damage your engine and your oil pump will suffer. Change it ASAP to the lower viscosity grade that could be managed by your engine (or keep the car in a warmed garage until spring. Your car, your choice). Check the owner manual. A too thin oil will lubricate worse. If you live in hot climates, 10W and 15W will perform better in summer Diesel vehicles will care of warming the diesel before to start and will refuse it unless the diesel is warm enough. If starting the car at morning takes ages, some of your glow plugs are probably broken and will need to be replaced. This can be a delicate operation. If stuck don't force it, go to a professional with the correct tools. Old plugs can be fragile and if they break inside the engine, it will be a very expensive mistake.
- nomel 4y ago> 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.
- pvaldes 4y agoNon 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.
- pshirshov 4y agoYou won't be able to drive at all without warming up in Siberia at -42. In fact it's very hard to start the engine from cold state. So everyone who was able to afford a pre-start heater were installing them. And those who were not were hooking up auto start timers (usualy paired with a crappy aftermarket alarm) so the cars were constantly starting in low temperatures (-30 and lower).
- Turing_Machine 4y agoIn the North Slope oil fields in Alaska, they just keep the trucks running 24/7 in the winter time.
- Glawen 4y agoDuring my trip in northern Siberia, while sipping my morning coffee, I saw a guy start up his lada niva by -40 the old fashioned way. He opened the engine bay, put a rug on his engine, took a blowtorch and lit it under the engine. He heated the engine oil pan and gearbox for 10 min, and then started his engine with a battery he brought with him.
- WalterBright 4y agoThe best thing you can do to make your engine last is change the oil regularly.
- Glawen 4y agoEngine 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 :).
- UncleEntity 4y agoThe 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…
- joecool1029 4y agoModern 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).
- WalterBright 4y agoI've never had an engine wear out on me and start burning oil.
- kosherhurricane 4y agoI 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 into different places that need it. Viscosity is not optimal, but it's good enough, as long as it's been changed appropriately, and not already a sludge. * At idle, the oil pump is at its lowest output. The fast idle at cold start mitigates that. Fast idle also warms up the engine faster than normal idle. Driving it will give it good output. * Engines do warm up slower when idling (<1k rpm) vs driven right away (2k+ rpm). Taken all this together, it's fine to start the engine when cold, let it idle for 30 seconds, and start driving. It's also fine to start the engine cold, and let it idle and warm up while you scrape the windshield and make a cup of coffee. Millions of people do both of the above, and their cars are fine. Ignore Business Insider, and maintain your cars as per its manual.
- Aloha 4y agoIdling all day comes with its own issues too.
- mustafabisic1 4y agoNow, if only we could get some winter in places where we're normally deep into winter by now :( Bosnia and Herzegovina here
- Giorgi 4y agoWhat? My car (which is quite old) has indicator of cold water, and recommends not to drive it till it is gone. It takes 3 minutes of idling in winter for that indicator to be gone. I assume other cars have it too. For that 3 minutes, RPM is high, you can see it at needle and you can hear it too. Once indicator is gone, RPM needle drops and noise becomes lower too.
- pugworthy 4y agoThe 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.
- exabrial 4y agoDon't listen to this nonsense as it's absolute baloney. I would ask the experts that design engines and oil rather than a one-off op-ed piece from a news source with a questionable reputation, a history of sensationalism, and zero applicable scientific qualifications. The primary reason you warm up your engine is because oil is more viscous at cold temperatures. All engine oils have cold flow characteristics and modifiers. It doesn't take a very large temperature rise for oil to thin out and begin filling the various galleries in your engine. Just a a few minutes will absolutely extend the life of your engine and prevent oil starvation on critical components. As a side note, as your oil ages, the viscosity modifiers break down; so older oil needs more time to flow properly, _especially_ if it's been 'cooked' at high temps from the summer. For your oil changes, try to change it between seasons, or if you do a yearly change, change it in the fall after the summer heat.
- sokoloff 4y agoMy 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.)
- BenjiWiebe 4y agoI agree with you, but that's essentially cold-thinning when it lets you run an otherwise-too-thin base oil.
- sokoloff 4y agoYes. This sub-thread was about “what happens when the additive package wears out; does the oil become full-time thicker or thinner than desired?”
- omginternets 4y agoModern synthetic oils are plenty viscous at subzero temperatures. Warming your engine isn’t necessary in a modern vehicle beyond taking it easy for the first 5-10 min of driving. (Nor will it appreciably decrease your engine’s lifespan.)
- kkfx 4y agoNot convinced. Sure an idle engine heat a bit slower than an used one, but all components around the engine, even a bit underneath, get a bit of heat. The cabin heated a bit allow easier removing of ice, plastic materials are LESS fragile due to the less freezing temp etc. I think such articles mean: do not burn fuel for nothing, do not leave powered on ICE for long period of time, and I agree with that, but try to stating it offer something really good or really bad to expected car service life is a bit ridiculous.
- Alan_Dillman 4y agoBunch of twaddle. I'm not doing it for the engine, I'm doing it so the windows thaw out, and partly so that the passenger compartment is warm. I'm doing it so I don't get in a friggin accident and kill someone. Oh yeah, just start it and drive off, very good. OP-ED obviously doesn't live in a real winter climate. As for stress on the engine, mine has a governor that won't let it exceed a certain speed until the engine temperature comes up.
- leoh 4y agoI wonder if a solution to this problem could be channeling gasoline through a convoluted pattern of tubes adjacent to a heating element
- walnutclosefarm 4y agoI 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 way warmer than 40F,and the engine has leaned the fuel mixture. I also wish the expert had addressed the real question in this warming scenario - which is how many piston cycles (crankshaft revolutions) you run with an over-rich fuel mixture. It's certainly true that engine warm-up takes longer at low rpms, but it also true that if you run at driving rpms, while the elapsed time to end the over-rich fuel will be less, you will have cycled the pistons many times more than at an idle. It's the piston movement he's tagging as the engine wear culprit, and it's not at all clear how many more piston cycles there really are, if you warm at an idle. It's not even clear there are more, thinking from first principles.
- iroddis 4y agoMany 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.
- jnsaff2 4y agoEspecially small diesels which take too long to warm up for passenger comfort.
- walnutclosefarm 4y agoYes, but the whole argument about washsing the oil off cylinder walls is irrelevant to diesels, as excess diesel lubricates, rather than dries cylinder walls.
- walnutclosefarm 4y agoCould be. I've never encountered one, and I think they would be a dead loser where I live. In fact, the thing I dislike most about our electric vehicle is that it's heaters are so wimpy. Probably wouldn't matter if I lived South of the Mason-Dixon line, but at -20F, they are awful.
- aetherspawn 4y agoThere is no oil where they claim it in the cylinder on Japanese engines, otherwise they would be burning oil (and they don't). At least not for the first 300,000kms or so. If the fuel can ever burn the oil, that's a really bad thing. Also the article claim about the power steering pump is completely wrong, as the pump runs no matter the speed or load of the pump; it will just pressure-relief through the pumps internal relief valve.
- gonzo 4y agoUnless it’s so cold that the pressure is higher than the PRV can … relieve. Same is true of the PRV at the oil filter. If you’re bypassing that, then you’re forcing unfiltered oil into the engine. Also, a too high oil pressure can wash out the babbitt on main and rod bearings. Agree that the article is bad. Wouldn’t say “no oil” as oil control in modern engines is good but not perfect and the rings (above the oil control ring) need some oil.
- Gordonjcp 4y agoMany 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.
- skeletal88 4y agoThe only reason why I let my car idle is because the windows are covered in frost outside and I don't want to daname them by scratching the ice off every day for 3-4 months every year. Better to heat the windows and let the ice melt from heat.
- skee8383 4y agoWhat a bunch of nonsense. He needs to give his degree back asap. It's called an oil pump. when your car is running it pumps oil to the parts that need it. only in really really cold temps where oil can actually freeze is it bad to even start the engine. how long you let it idle doesn't matter. it's literally just sitting there running the oil pump and and circulating oil to where it needs it. If idling an engine in the cold will hurt the engine then so too will driving it because the exact same thing is happening either way.
- bloomingeek 4y agoA two minute warm up is good for cars in winter, even with synthetic oil. Slow-ish speeds for a couple of miles will warm up the engine nicely. Keep in mind, when you start you vehicle on a cold morning, it high idles for a few minutes. This is by design. Great and interesting replies as usual. For my two cents, don't trust the dealer where you bought your car. My wife and I bought a new Ram truck in 2021, I asked the salesmen what are the engine break-in best practices. He said he didn't know, no surprise there, so he called the service manager. The manager told him to tell me there is NO break-in required for these new "crate engines" these days! I was shocked, so after I returned home I read the manual. It had concise instructions for breaking in both the engine and the transmission, which I was careful to do. There is plenty of stories on the web about the engine in my truck having upper engine problems, perhaps they believed the dealership.
- gonzo 4y agoOnce upon a time, before fuel injection and effective manifold heat, cars were not very drivable when cold. The gasoline would not vaporize well in the cold carburetor so the “choke” had to be set to enrich the mixture. When the vaporized fuel interfaces with cold metal in the intake manifold and intake passages in the head(s), the fuel condenses out of suspension, creating a very lean mixture, despite the choke being set. Combine this with dropping revs from leaving a stop in a manual transmission car, and stalls were frequent. The solution was to allow the engine to “warm up”. I have an old Toyota fj40 that reminds me of the before times when it’s cold. The author of the article got many things wrong. Washing the cylinders is a thing, but the cylinder has just had a combustion event in it that runs at 2600°F or higher. There is very little oil on the cylinder walls during the “power stroke” in a 4-cycle engine. The walls are reoiled on the exhaust, intake and compression strokes. A study by the Society of Automotive Engineers (SAE) found that the temperature of the combustion chamber walls (the top section of the cylinder wall), specifically, ranges from 265° F under limited throttle to 475° F with the throttle wide open. https://www.sae.org/publications/technical-papers/content/930217/#:~:text=Average%20combustion%20chamber%20surface%20temperatures,C%20to%20258%20deg https://www.sae.org/publications/technical-papers/content/93.... The flashpoint for motor oils is 300-475° F, which is why you can maintain a thin film in the cylinder walls. Excessive idling will foul spark plugs and valve seats.
- dmtroyer 4y agoLots of experts in the comments on this one.
- glennvtx 4y agoI can say from plain observation this is wrong, On many engines you can audibly hear piston slap, older worn crank bearings make a banging noise when the engine is cold. The article cites fuel efficiency, but fuel efficiency is not what most people are concerned with, they care about the longevity of their vehicle.
- supergirl 4y agoexcept some cars even have a light in the dashboard that stays on until the engine is warm. I trust the manufacturer knows a thing or 2 about this