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Discussion Starter #1 (Edited)
OK...I was speaking with someone last night who knows 1000 times more than I do about mechanical engines. There were 2 things that I just didn't agree with him on. The first thing was, that modern day cars don't need to warm up. (OK, maybe I am wrong about this. So I'll give it to him. (But it just doesn't make sense to me that an ice cold ANYTHING-mechanical, doesn't work better when it's at least slightly warmed.)) But OK...this guy designed compressors for airlines so he obviously knows WAY more than I do. :confused:

But then he said that letting an engine idle for long periods of time, can actually harm the engine. Now this I absolutely disagree with!!! :eek:
In the Winter I let my car sit warming up in the driveway for AT LEAST 15 mins. I just like getting in a warm car plain and simple. Have done this for the past 25 yrs with all of my cars.
Just interested in other's opinions about this. :cool:
Thanks!
Keith
 

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I read that certain components of your oil that protect from metal to metal contact only work after they warm up to 30-35 deg c. Mollybendium etc.

I think it’s OK to drive almost immediately if it’s possible to keep from jack rabbit starts, reving lower than say 4 k.

The car needs to be very warm to drive in stow storms as we often melt and defrost snow and blow fog our entire drive up here in Canada.

Driving blindly in a cold foged up car is reckless.

I’m not impressed by how much gas this car uses at idle. I’m assuming it’s waisting gas warming the cats keeping the exhaust clean.
 

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My 2014 never leaves my driveway until it has run at least 3 minutes period summer/winter . doesn't matter
And if the windoze are frosted up it idles until the windows are clear. starting your car and putting it straight into gear and driving away is stupid in my opinion. but opinions are like buttholes ...everybody has one.
 

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Engine idling is, in fact, bad for engine longevity. More specifically, it punishes the oil.

I had a used engine oil sample analyzed by a laboratory, and the flashpoint was significantly lower by idling the engine warm than the other engine oil samples that were taken after a drive to warm up the engine oil.

Long idling results in increased fuel content in the engine oil, which means the engine oil mixture becomes easier to ignite.


However, my take on warming up the engine is that I find it more beneficial to warm it up by idling.

Spirited drivers like me who are VERY eager to see high load, high RPM use will find long-term benefit of idling an engine warm (versus driving the vehicle to warm up the engine), as the engine will be closer to normal operating temperatures, meaning the engine will be more likely to be at the correct tolerances intended to be operated in high load and/or high RPM use. So despite the loss of fuel efficiency and having engine oil that will likely have decreased lifespan, I consider this a good trade-off for improved engine protection under operating conditions I expect to put the engine through while actually driving.


So when it comes to efficiency, driving to warm up is best, but at the cost of avoiding high load and/or high RPM use until the engine sees normal operating temperatures. But for spirited driving, high load use, and/or high RPM use, idling an engine warm does have its benefits.
 

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Discussion Starter #6
Thanks for all of the input! :cool:
Not concerned about the oil. Even though they put in the syntho oil, I still have it changed every 3K miles.

And yes, I'm a VERY spirited driver. ;) So warming it up, for me, is a must. (Even in the Summer months I'll let it sit for about 5 mins.) :D

Thanks again!
-Keith
 

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In my opinion, it's also good to idle and cool down (with electric fan cycles) extremely hot engines, before shutting them down.

I think this practice will minimizes distortion from uneven cooling and hot spots.
 

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Discussion Starter #8
In my opinion, it's also good to idle and cool down (with electric fan cycles) extremely hot engines, before shutting them down.

I think this practice will minimizes distortion from uneven cooling and hot spots.
Good point.
Thanks,
Keith
 

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I think a similar thread had some people getting pretty feisty about the subject. I utilize the blue light to signal that the motor is properly warmed. It also coincides with the revs kicking down. Knock wood, no oil consumption issues to date with 20k. I’ve never had to add as yet between changes. I had my last vehicle for over 230k, and never used more than a half a quart in all that time. I also don’t thrash my car, and have no need for excessive idling. I’m going to continue my practice.


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I think a similar thread had some people getting pretty feisty about the subject. I utilize the blue light to signal that the motor is properly warmed. It also coincides with the revs kicking down. Knock wood, no oil consumption issues to date with 20k. I’ve never had to add as yet between changes. I had my last vehicle for over 230k, and never used more than a half a quart in all that time. I also don’t thrash my car, and have no need for excessive idling. I’m going to continue my practice.


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The blue coolant temp light is a good indicator to take it easy till it turns off. Just for an FYI that happens with a coolant temp of 120*F according to my ScanGauge II.
 

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It usually turns off relatively quick. Even with the very low temperatures of recent, it’s about 4 or so minutes. Good to hear the actual temperature though. Gives me the time to get situated in my vehicle. I really only do this after the car has been sitting overnight or for about 7 or so hours.


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The blue coolant temp light is a good indicator to take it easy till it turns off.
That's the practice I also go by. Gradual accelerations and no hi-revving until the Blue goes off. I'm fortunate to have a heated garage so even on zero-degree mornings my car starts out at about 43° so it only needs about 2 mins to warm the blue light away. Even after parked outside at work all day in sub-zero, Blue goes away after about 4 minutes tops.

A few years ago, I heard the "Car Talk" guys on radio take a listener question about excessive idling and they were of the opinion that extended idling on a modern car really does little to no harm because of the on-board computers keeping things in balance (other than wasting fuel since you're getting Zero MPG). So if it's just cold, I'll idle just a minute or so before taking off, but if it's been snowy I'll let it run while I clear the windows and other surfaces of the ice/snow, usually 5-10 minutes tops.
 

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Discussion Starter #13
OMg! BEST RADIO SHOW EVER!!!! That was the most educational and HILARIOUS show. Miss it.
Thanks for bring them up!
-Keith
 

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this (‘16 crosstrek) is my first cvt. i find that the rubber band is eerily quiet most of the time, probably the quietest drivetrain i’ve ever owned, but when it gets cold (canada), it makes some buzzing noise under load. not sure if the noise is a bad thing, but i’d rather not find out, so i warm the car up a bit more when it’s cold. (otherwise, it’s usually about as long as it takes me to buckle up, check the mirrors, and put it in gear.) but i also go easy on the throttle for the first couple of minutes.
 

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Yesterday was a very good day to be driving a Crosstrek around here. Even the airport was completely closed for a while. My afternoon commute home took over 2 hours (instead of the usual 50 mins), and other cars were getting stuck all around me while I easily kept a move on. I let it warm up good while I cleaned off all the snowdrifts. Crosstrek seems right at home in this kind of weather.

 

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Mostly, everything depends on the weather in your country, if it is winter and it is really cold, than you should wait for it to warmup, otherwise it can end very bad for your car. Also it depends if it is diesel or petrol. Usually petrol is better because it can resist to colder temperatures. Unlike petrol, diesel is "weaker" and you need to wait a few minutes to warm up, then you can go wherever you want. I am working at Car Rental in Lviv, Ukraine - Cheap & Best car hire | NarsCars and each engine has their advantages and disadvantages. Petrol is better for winter, diesel is better for work.
 

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Warm it up properly if you can. At the very least go easy on the gas. The low friction rings need time to properly expand.

I remember a discussion about variable valve timing being adjusted for maximum compression in an attempt to allow compression ignition to speed warming of the engine, AKA knocking.

Additives like molybdenum don’t lubricate at temperatures below the 30deg C point.
This is the oil temp where the blue light switches off.
 

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I take many long road trips and stay overnight next to the interstates. The one thing I DON'T do is start up, and jump onto the highway doing 70+ mph within minutes. But I also don't let the car idle for 15-20 minutes even in the coldest weather. I will note where there might be a Dunkin Donuts or similar nearby to get the morning go-go juice and drive there. It might be a few minutes out of the way, but it's better than abusing the engine right away.
 
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