Warming up the engine on cold starts

So if the cold-rich-running washes away the oil from the cylinder walls, how much more damage might be cause by putting the cold engine under load (as the oil continues to get washed off the cylinder walls), just in an effort to warm it up faster to make it run lean (and be properly lubricated sooner)?

Wouldn't under-load/poorly-lubricated short driving be just as bad as no-load/poorly-lubricated extended idle?

I'm now wondering if the difference between the two is negligible.

Yes, but the point is the poorly lubricated time is shorter when you drive rather than idle, so the overall "damage" is reduced.

And I agree, it's not that big a deal one way or the other. There is a period of poor lubrication no matter what.

By the time I'm settled in, buckled up, phone mounted, sunglasses on, and music set, I drive.
 
So if the cold-rich-running washes away the oil from the cylinder walls, how much more damage might be cause by putting the cold engine under load (as the oil continues to get washed off the cylinder walls), just in an effort to warm it up faster to make it run lean (and be properly lubricated sooner)?

Wouldn't under-load/poorly-lubricated short driving be just as bad as no-load/poorly-lubricated extended idle?

Yes, if you floor it when the engine is still cold, it would wear out faster than idling.
The point is to put a light load on it, which will warm the engine significantly faster without stressing the engine.
 
Yes, if you floor it when the engine is still cold, it would wear out faster than idling.
The point is to put a light load on it, which will warm the engine significantly faster without stressing the engine.

Don't have to floor it.

Any RPMs above idle/extra load are incremental wear.
 
Don't have to floor it.

Any RPMs above idle/extra load are incremental wear.

Luckily, the ICE is so inefficient, most of the energy is wasted as heat instead of mechanical work. This is why driving it with light throttle inputs and light engine load is preferred.
 
I keep hearing about this blue light. I have a 2017 GT no tech and I do not have this feature.
 
The blue dash light in my 16.5 stays on until the cat is warmed up or something.
For the first few seconds after cold start the throttle position shows up to 32% on my scangauge and the exhaust sound is pretty loud. Then it settles down to a more subdued fast idle maybe TPS around 18%.

Regular idle after the blue light goes out after I drive about a block is typically 12%.
 
Do you have an actual engine coolant temperature gauge (meaning a real permanent analog gauge in the right pod - not the selectable digital one)? If so, and I think a GT trim from 2017 would, then there is no temperature blue/red light (since the engine coolant temperature condition is always visible).
 
I have a 2017 Grand Select that has a real permanent analog coolant gauge and it does NOT have the blue (cold) light.
 
When it is below -5 or so Celsius I wait 10 seconds then drive easy until the blue light turns off, -20 and below wait almost 30 seconds, otherwise I start and go - done this with all vehicles (although this only one with blue light)!
 
I keep hearing of this blue light. I have a 2017 GT and I don't have it.
Hmmm! I have a 2017 GT with Premium Package with the blue light. It disappears once the engine has sufficiently warmed up usually in less than 5 minutes.
 
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Hmmm! I have a 2017 GT with Premium Package with the blue light. It disappears once the engine has sufficiently warmed up usually in less than minutes.
Don't have to floor it.

Any RPMs above idle/extra load are incremental wear.
Flooring a cold engine has to be hard on it.I don't like to go above 2500 or so when driving a cold engine.AS far as idling to warm it in cold weather,I do and 15- 20 minutes is common on very cold days.
As far as increased cylinder wear,this isn't the old carburetor and choke system of yesteryear.I have to believe that the direct injection puts the atomized fuel more to the center of the piston and less to the cylinder walls.Another issue is that piston ring sealing relies on cylinder pressure (which increases under load).If gasoline is washing the oil from the cylinder walls I'd rather have a lower cylinder pressure forcing those rings against the cylinder walls when idling versus higher cylinder pressure from driving it cold.
Just my way of looking at it.Plus the tranny likes it better and a warm car can be a nice thing.The tailpipes also don't get sooty.Could probably debate this until the cows come home.
 
Flooring a cold engine has to be hard on it.I don't like to go above 2500 or so when driving a cold engine.AS far as idling to warm it in cold weather,I do and 15- 20 minutes is common on very cold days.
As far as increased cylinder wear,this isn't the old carburetor and choke system of yesteryear.I have to believe that the direct injection puts the atomized fuel more to the center of the piston and less to the cylinder walls.Another issue is that piston ring sealing relies on cylinder pressure (which increases under load).If gasoline is washing the oil from the cylinder walls I'd rather have a lower cylinder pressure forcing those rings against the cylinder walls when idling versus higher cylinder pressure from driving it cold.
Just my way of looking at it.Plus the tranny likes it better and a warm car can be a nice thing.The tailpipes also don't get sooty.Could probably debate this until the cows come home.

Yikes.....15-20 minutes? Also remember, the lower cylinder pressure is creating less ring seal, so you might have more blow-by, which could wash oil away further down the cylinders, causing more wear (just a theory).

No, I don't have a CX5, but I have a Explorer Sport w/ 3.5 ecoboost. On very cold days (-15F), I'll let it idle 5 minutes at most. It's really however long it takes me to get buckled in after remote starting while walking through the parking lot at work. In mornings when garaged @ home, really cold nights get block heater and maybe 1-2 minutes of warmup.

I wonder if anyone did a test to compare idling to warm an engine vs. driving easy. You see it quite often that it is recommended to drive easy vs. idling to warm up, but is there actual data (engine wear analysis) to back it up?
 
I keep hearing of this blue light. I have a 2017 GT and I don't have it.
I've posted this before, but for your edification, here is the blue light on a 17 GT

IMG_20190729_145115437.jpg
 
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Yikes.....15-20 minutes? Also remember, the lower cylinder pressure is creating less ring seal, so you might have more blow-by, which could wash oil away further down the cylinders, causing more wear (just a theory).

No, I don't have a CX5, but I have a Eoutxplorer Sport w/ 3.5 ecoboost. On very cold days (-15F), I'll let it idle 5 minutes at most. It's really however long it takes me to get buckled in after remote starting while walking through the parking lot at work. In mornings when garaged @ home, really cold nights get block heater and maybe 1-2 minutes of warmup.

I wonder if anyone did a test to compare idling to warm an engine vs. driving easy. You see it quite often that it is recommended to drive easy vs. idling to warm up, but is there actual data (engine wear analysis) to back it up?
I hear what you're saying and when I was working (now retired) the car only got a few minutes warmup after sitting in a cold parking lot all day.That was normal.However when I'm at home my car sits outside (no garage at present nor do I have a block heater) so it can warm while I get ready to go.If the car is covered in snow or totally coated in ice it definitely gets warmed up .I like the ice to melt off the windows.Scraping is a b**** and can ruin wiper rubber if not careful.Also can scratch windshield from grit on windshield under the ice.As said before,the tranny "likes it" and shifts smoother.In previous cars with regular power steering (non-electric) it steered easier and smoother.Hydraulic systems" like" warm fluid.
Really,the car is a machine to SERVE my needs and I'll keep it well maintained but use it to COMFORTABLY serve my needs.I see no reason to place it on a pedestal and worship it and worry about possible increased wear or extra fuel usage.As stated,it serves me and i'm not going to freeze my ass off in a frigid piece of steel and glass because of the prevailing notions of the masses on such matters.
While I'm on a roll and the subject of lubrication /oil is mentioned,ponder this.How warm do you think the oil is when that (CX-5) blue light goes off at 130*F.I bet that if you felt the oil pan at that time it'd barely be warm if at all and nowhere near 130*F .Coolant temp and oil temp don't track the same starting out so I'd rather the oil flow a little better before being put under load.Just the way I see it.
 
[snip]
.Could probably debate this until the cows come home.

Yeh, you can copy/paste THAT statement into a lof of conversations.

So little of this stuff can be quantified outside of a shop or a lab.
 
Really,the car is a machine to SERVE my needs and I'll keep it well maintained but use it to COMFORTABLY serve my needs.I see no reason to place it on a pedestal and worship it and worry about possible increased wear or extra fuel usage.As stated,it serves me and i'm not going to freeze my ass off in a frigid piece of steel and glass because of the prevailing notions of the masses on such matters.
Well said. I've been warming up cars my entire life. I've read data and seen reports... yea, I have never once had an engine failure. Never had fuel dilution issues. Frankly if a car gets damaged by sitting in my driveway idling... s***, for an HOUR... then it's a POS in my mind.
I just don't believe any damage results from a car idling to warm up that is going to effect the car long term. Maybe long long term but I don't keep cars past 150K.
 
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