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

businessinsider.com

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

#101

Post by jcampbell1 »

gooseyman wrote: post #65
jcampbell1 wrote: post #48

Earlier quoted context omitted.

I worked at the engine plant in the early 2000s that made the 4.6l v8 that was in Crown Victoria for cop cars and cabs. The cop/cab version of the engine was different in that it had a highly polished timing chain for exactly this reason.

This is super interesting as a person who is interested in cars, but by no means a mechanic. What does polishing the timing chain accomplish? Or is it more “accurate” timing?

The timing chain is splash lubricated and at idle there isn’t enough oil pressure to produce much splash. The high polish reduces friction particularly when there is little oil.

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

#102

Post by avereveard »

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 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 differentials aren't, but you don't have a good way of warming them up while standing still, so drive off slowly and carefully without asking full torque from your engine, and it will help warm the whole thing.

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

#103

Post by dghlsakjg »

MadScott wrote: post #70
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…

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.

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

#104

Post by Giorgi »

What? 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.

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

#105

Post by raverbashing »

psychphysic wrote: post #9

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…

Exactly

I love how some people get precious about cars and engines, something like "if you idle it for too long you're shortening its lifespan" and even if it's moderately true my answer would be "Yeah, so what? It's a clunky block of 19th century technology, who cares?"

Yeah sure, you don't need it to sit idle for something like 30 min, just wait for it to get a bit warm then drive away. Worrying about this will cost me more than not worrying.

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

#107

Post by UncleEntity »

FooBarWidget wrote: post #95
psychphysic wrote: post #9

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'll to go great lengths to avoid turning on the car's heater.

You know, heat is a byproduct of the combustion process…

—edit—

And these people who won’t turn on the AC to save gas end up messing up the aerodynamics and making the vehicle less efficient while also suffering.

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

#108

Post by exabrial »

Don'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.

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

#109

Post by brookside »

FooBarWidget wrote: post #95
psychphysic wrote: post #9

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…

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 stop sign, except for regen, as you mention. And is indeed obnoxious for other drivers if you are braking way before a sign.

Hypermiling is a good idea, but it's a trap to to slip into an orthorexia-type mindset about efficiency - imbuing virtue into deprivation. Going to "great lengths" to not turn on your car's heater, in addition to being 100% pointless if your ICE engine is running, is an asshole move if other people are in the car. I think it's worth it to fight the feelings of superiority you allude to in your last sentence.

I say all of this as somebody who thinks 95% of drivers would be best served by a Prius or Leaf.

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

#110

Post by UncleEntity »

sokoloff wrote: post #39
sschueller wrote: post #6

"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…

Note 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.

I saw on the YouTubes that they can’t even physically turn the motors over without preheating due to close tolerances of the engine guts.
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