How many of us oil nerds still "warm up" your car?

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Originally Posted By: Stewart Fan
My wife likes the "start and dart". Her car is in reverse and backing out of the driveway a split second after its started.



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Originally Posted By: Artem
Originally Posted By: Stewart Fan
My wife likes the "start and dart". Her car is in reverse and backing out of the driveway a split second after its started.



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Its true though. its a simultaneous motion, the key has barely reset back into its "on" cradle position and the thumb has depressed the gearshift and it is in R while the foot comes off the brake headed to the gas.. Real talk.

As to the defrosting, crack open a window FFS. Then blow the defroster full cold, then hot as it warms up. Then close window.

i know, i know.. we do not want to have to crack open the window.. but the car's own devices dont do much until 1-5 minutes after taking off.

Also, flick the wipers unless its snow frozen.....
 
Originally Posted By: Stewart Fan
My wife likes the "start and dart". Her car is in reverse and backing out of the driveway a split second after its started.



Yeah, mine too. I swear she's backing up before taking her hand off of the key. The reverse lights look like they're on before the starter shuts off.
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Originally Posted By: grampi
Originally Posted By: hattaresguy
Waste of gas with a modern car.


...he says until he runs into something due to refogged/refrosted windows because he didn't let the car run long enough to generate heat from the defrosters...


Letting a vehicle run to thaw the windows so you can see is quite different than letting it idle for no reason every morning, just because.

Oh BTW, if you keep your vehicle in a heated garage, frost doesn't get on it! Amazing!
 
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Originally Posted By: slammds15
Originally Posted By: IndyIan
Originally Posted By: grampi

Yes, I would also like to know where these people are buying their vehicles with these magical HVAC systems that totally defy physics...

It came standard on my Neon... But seriously, the inside of my windows are rarely frosted when I get in my car in the morning. To keep them clear I blow any temperature of air over my windows. At no point from 0F air to 100F air do they fog up as I drive and the car warms up... It doesn't defy physics and no AC is needed either(mine broke 5 years ago).


So what you are saying is that there is no fog to begin with, you have the defroster on, which is exchanging air in the vehicle, not allowing moisture to saturate the air and condense on the "cold" windshield. I can agree to that. With no temperature or humidity difference no change will be noticeable. Remember your heater core receives coolant all the time whether your engine is "up to temp" or not. So even a few degrees will make a big difference.

Yep, that's exactly it.
Originally Posted By: slammds15
I love the snow brush post btw, I own one but if it's that bad I tend to be lazy and put it on defog till it melts or I run out of washer fluid lol

The odd time I'll do the washer fluid thing too if I'm running late... And inspite of Grampi's opinions, the outside of the window will also clear light frost quite quickly at 55 mph before the car is warmed up as well. Sublimation works pretty well at highway speeds.
 
Originally Posted By: 45ACP
As to the defrosting, crack open a window FFS. Then blow the defroster full cold, then hot as it warms up. Then close window.

i know, i know.. we do not want to have to crack open the window.. but the car's own devices dont do much until 1-5 minutes after taking off.


Yep, helps your breath from fogging the glass.

I will admit that I've pulled an Ace Ventura a couple times after hitting the washer too soon (frosted up!).
 
Three years ago, I discovered Prestone de-icer washer fluid. Whoever came up with this deserves a Nobel Prize! It will clear heavy frost or half an inch of snow in ten seconds on a cold windshield.
 
I give my car about 30 seconds, then I'm down the road, driving easy for the first couple of miles. My car stay's in an insulated, unheated garage, stay's about 40 degree's most of the time.
 
Originally Posted By: IndyIan
Originally Posted By: slammds15
Originally Posted By: IndyIan
Originally Posted By: grampi

Yes, I would also like to know where these people are buying their vehicles with these magical HVAC systems that totally defy physics...

It came standard on my Neon... But seriously, the inside of my windows are rarely frosted when I get in my car in the morning. To keep them clear I blow any temperature of air over my windows. At no point from 0F air to 100F air do they fog up as I drive and the car warms up... It doesn't defy physics and no AC is needed either(mine broke 5 years ago).


So what you are saying is that there is no fog to begin with, you have the defroster on, which is exchanging air in the vehicle, not allowing moisture to saturate the air and condense on the "cold" windshield. I can agree to that. With no temperature or humidity difference no change will be noticeable. Remember your heater core receives coolant all the time whether your engine is "up to temp" or not. So even a few degrees will make a big difference.

Yep, that's exactly it.
Originally Posted By: slammds15
I love the snow brush post btw, I own one but if it's that bad I tend to be lazy and put it on defog till it melts or I run out of washer fluid lol

The odd time I'll do the washer fluid thing too if I'm running late... And inspite of Grampi's opinions, the outside of the window will also clear light frost quite quickly at 55 mph before the car is warmed up as well. Sublimation works pretty well at highway speeds.



Laws of physics are not opinions, and as much as you claim your vehicles will voilate those laws, I'm afraid it's just a figment of your imagination...defrosters blowing cold air will not clear windows....
 
In our GM vehicles the defroster will indeed clear the windows when very cold DRY air blows over it. This works in quite cold weather as low as the high teens. Then in a mile or so the heat kicks in and it's all good.

But absolutely, cold air can indeed dry a misted window. As a certified structural dryer I can also tell you we've used cold air for decades to dry wet houses. Heat is much better but those same laws of physics dictate that the kinetic energy of rapidly moving air will allow it to absorb a bit of moisture as it blows coldly past!
 
Originally Posted By: SteveSRT8
In our GM vehicles the defroster will indeed clear the windows when very cold DRY air blows over it. This works in quite cold weather as low as the high teens. Then in a mile or so the heat kicks in and it's all good.

But absolutely, cold air can indeed dry a misted window. As a certified structural dryer I can also tell you we've used cold air for decades to dry wet houses. Heat is much better but those same laws of physics dictate that the kinetic energy of rapidly moving air will allow it to absorb a bit of moisture as it blows coldly past!


OK then maybe you can explain to me why in the nearly 40 years that I've owned vehicles, NONE of them had defrosters that would clear windows until they were blowing warm air, or at least air that was warmer than the ambient air temp?
 
Originally Posted By: SteveSRT8
In our GM vehicles the defroster will indeed clear the windows when very cold DRY air blows over it. This works in quite cold weather as low as the high teens. Then in a mile or so the heat kicks in and it's all good.

But absolutely, cold air can indeed dry a misted window. As a certified structural dryer I can also tell you we've used cold air for decades to dry wet houses. Heat is much better but those same laws of physics dictate that the kinetic energy of rapidly moving air will allow it to absorb a bit of moisture as it blows coldly past!


Spot on. I did it yesterday, in fact...got in my work truck, started the engine (a 7.2 litre Caterpillar diesel that takes a while to warm up its six gallons of oil & twelve gallons of coolant), did my assorted paperwork. While I did, the windows fogged over from my breath. Crank the defroster (engine still cold, temp gauge not off the peg yet), the windshield & side glass cleared in about 90 seconds.
 
Originally Posted By: grampi
Originally Posted By: SteveSRT8
In our GM vehicles the defroster will indeed clear the windows when very cold DRY air blows over it. This works in quite cold weather as low as the high teens. Then in a mile or so the heat kicks in and it's all good.

But absolutely, cold air can indeed dry a misted window. As a certified structural dryer I can also tell you we've used cold air for decades to dry wet houses. Heat is much better but those same laws of physics dictate that the kinetic energy of rapidly moving air will allow it to absorb a bit of moisture as it blows coldly past!


OK then maybe you can explain to me why in the nearly 40 years that I've owned vehicles, NONE of them had defrosters that would clear windows until they were blowing warm air, or at least air that was warmer than the ambient air temp?


I think Steve is referring to windows fogged on the inside and you are perhaps referring to frosted windows or those fogged on the outside.

I agree with you, it's practically impossible to defrost a windshield with cold air.
 
Hey, I live in FLORIDA, it's not icy down here much! What is frost?

But yes, many times our trucks have the doors and/or windows down in the AM as we load out the boys for the day. The interior windows will fog over quite heavily.

And ice cold air does indeed de-fog them quite well.
 
By physics, if the engine is running, the air blowing out of the vent is going to be higher than the ambient temperature. Think about it.
 
Originally Posted By: cchase
Originally Posted By: grampi
Originally Posted By: SteveSRT8
In our GM vehicles the defroster will indeed clear the windows when very cold DRY air blows over it. This works in quite cold weather as low as the high teens. Then in a mile or so the heat kicks in and it's all good.

But absolutely, cold air can indeed dry a misted window. As a certified structural dryer I can also tell you we've used cold air for decades to dry wet houses. Heat is much better but those same laws of physics dictate that the kinetic energy of rapidly moving air will allow it to absorb a bit of moisture as it blows coldly past!


OK then maybe you can explain to me why in the nearly 40 years that I've owned vehicles, NONE of them had defrosters that would clear windows until they were blowing warm air, or at least air that was warmer than the ambient air temp?


I think Steve is referring to windows fogged on the inside and you are perhaps referring to frosted windows or those fogged on the outside.

I agree with you, it's practically impossible to defrost a windshield with cold air.


It's been my experience that a cold defroster will not either clear frost on the outside, or fog on the inside...
 
Originally Posted By: Vikas
By physics, if the engine is running, the air blowing out of the vent is going to be higher than the ambient temperature. Think about it.


How do you figure? Before the engine starts to warm up, it, along with the coolant, is the same temp as the ambient air temp...even when the engine's running...
 
Originally Posted By: grampi
How do you figure? Before the engine starts to warm up, it, along with the coolant, is the same temp as the ambient air temp...even when the engine's running...


This is getting nuts. Defroster on full blast even with cold air AND THE WINDOW CRACKED OPEN A BIT HELPS air flow. And that air flow will HELP get the frost/fog off the windows.. obviously it wont melt ice. When the air starts to warm some cars warm up very very quickly and i dont know how they do, others take awhile, then the air gets warm and the ice outside can melt through HEATED air blown on same windshield. And yes, i know that running defroster is supposed to "take away from the heat available" but when the engine is under load, it warms up faster (unless you cant see when you start the car, which may require wiping) BUT 1. Airflow, from the window a crack open and the defrost running at ANY temperature, IT USUALLY PROGRESSES FROM COOL TO HOT AS PER PHYSICS combined with 2. Window a crack open GREAT help from equalizing ambient humidity INSIDE car to outside, which is why fog is there in the first place.. plus rear defroster on, etc.. will get you going.

Flick the wipers, too..

Also please recall that "having the window open will also help the AC flow and assist on a HOT day." Same reason.. vacuum/airflow. Then you close the window and saved ~3x the work of if you were to try to force it out on Recirculate, or the setting that appears colder, never could figure that out.
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