Yes, warming up your car before driving in cold weather can damage the engine

We don't get as cold as Minnesota but sub-zero temperatures (not "wind chill" either) are normal every winter. Definitely no heated garage here and I don't think they're common at all unless someone has converted their garage or uses it as a "shop". Anyway, I added those insulation panels to our garage door a couple years ago and took some measurements. Needless to say, they don't help in the winter but do help in the summer (door faces west). Here's some measurements I took:

26º F outside temperature | 23º F
49º F center of floor | 46º F
39º F center of door | 45º F
48º F center of ceiling | 47º F

I guess they actually worked on the door itself. It was colder outside after so my second readings were lower as well.

Just re-checked the temperature forecast and the high temperature tomorrow is supposed to be 1º F 🤪 That's in the middle of the day.... At 9am tomorrow, the temperature is expected to be -6º F.
That's interesting. My attached garage is fully finished with drywall and about 700 square feet. The door faces south and the sun really beats down on the door in the summer months where outside temps often get up in the high 80's. A couple of years ago I installed those Styrofoam insulating panels on the roll-up aluminum door from a kit I bought at Lowes. In the winter months the garage now stays between about 50-58 degrees on average even when it is in the 20's and 30's outside. However the insulating panels are less effective in the summer, probably due to the amount of direct sun that the door receives. They still cut at least 10 degrees as I can feel a lot less heat radiating on the inside of the door now.

We get a little snow here, I'm up at 6000 feet but the county puts sand on the roads instead of salt so that is not an issue. I just have to sweep the garage floor about once a week to get rid of the sand and gravel that accumulates.
 
I have experienced much the same with my Toyota Camry. Granted I don't live in a "cold" climate. But in the Winter here it can get into the low 40's in the morning. It's about a 3-1/2 mile drive from my house downhill to get to town. The car basically coasts all the way down.

This time of year the temperature gauge won't move off "COLD" the entire way. As soon as I get to the bottom, and give it some throttle, the needle starts to climb rather quickly, because it's under a load, and not coasting and idling.

My other 2 vehicles don't experience that as drastically as the Toyota does. For some reason they just don't build up heat as fast as most other models.

On the Toyota forum there are numerous threads from people living in cold climates, complaining how it's difficult to get any heat out of them. And it generally appears to be a problem the dealers can't seem to do anything about.
Only solution is idling, or block heater.
I will never forget thanksgiving 2019. We have spent 5 days at in laws in Vegas and parked Sienna at Denver airport. We get back, it is 10 degrees, 9pm. Our 7 month old want to breastfeed as soon as we got in the car. I am idling car at 2-3,000rpm, other kid is under blanket and my jacket. The 7 month old is under other blanket, my wife’s jacket and some other stuff I could find, and car had ice on windows from inside.
I always claimed these Toyota’s are made to drive 10 miles from home and back. Anything else is too much to ask.
 
I'll run the best oil I can buy, and the best gas I can get, and give it regular scheduled maintenance etc etc.

But in the end my truck is a tool, meant to serve me and make my life easier, and it does that best by warming up first on a harsh winter day. If that means it dies 1 month earlier, so be it. Chances are I'll have moved on to the next truck by then anyway simply because my needs in a vehicle seem to change every few years.
 
I agree. Why would idling strip away oil whereas driving wouldn't? Oil pump is operating whether idling or driving.
It has long been discussed that in cold conditions, and even when some fuel additives are used, there can be fuel condensate that dilutes or washes oil films on cylinder walls.

Even under the dynamic, hot, severe conditions of combustion.

No new theories or science there. No load, no heat, more condensation (fuel or water) or low level localized dilution, thinner films, more wear…
 
It has long been discussed that in cold conditions, and even when some fuel additives are used, there can be fuel condensate that dilutes or washes oil films on cylinder walls.

Even under the dynamic, hot, severe conditions of combustion.

No new theories or science there. No load, no heat, more condensation (fuel or water) or low level localized dilution, thinner films, more wear…
And oil doesn't fog as nicely off the crank thows and mains spillage with a predicted cold start 700 - 900cSt* This is the only action that lubes the cyl and piston underside
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*there will be viscosity moderating through immediate shear and windage
 
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Wideband Air Fuel Ratio sensors came out since 1992. The Honda Civic was the first to use them.

But not all vehicles are equipped with it.
I assume you are referring to the D15Z1 specifically? (I had to look it up). It notes several optimizations for fuel economy, this being one of them. My understanding, based on the Wiki, was that this was the only engine in the Civic that received that treatment.
 
I assume you are referring to the D15Z1 specifically? (I had to look it up). It notes several optimizations for fuel economy, this being one of them. My understanding, based on the Wiki, was that this was the only engine in the Civic that received that treatment.
Yes. You are correct.

To identify, the sensor would have 5 wires.
 
Thoughts, Opinions?

I was going to post this but you beat me too it.

I’m still trying to understand the part about when the car is not moving then oil is dripping back down. Now I will admit I am no mechanic by any means and don’t have the knowledge as others, but I always thought if the motor is running regardless if sitting there idling or at full throttle, oil is circulating and doing what it is supposed to do
 
Yep, but try telling that to the wife.

"You will have to drive in a cold car for 120 seconds before the heater starts blowing and the seats warm up, so we can get an extra 500 miles out of this car"

Let me know how that works out :)

hey, you are the one who married such crazy. LOL
 
I have seen cold seized 2 stroke snowmobile engines. Piston expands faster than cylinder.
We are talking about real winter temps and operator starting and hammer down riding squeaking pistons.
Both liquid and air-cooled engines.
I warm up all my motors and if short warm up easy on the throttle until temp gauge gets up to normal. IE I don't' start and pull out onto the highway or make the other turn and pull uphill for 1.5 miles on a cold motor. Taking the flat route, I'll short warm up and go easy on the throttle.
Time and money are a 2-way street in certain conditions.
Yes. 2 strokes are a different animal. I always allow all of my 2 stroke engines, (power blowers, hedge trimmer, and chainsaws), to fast idle for several minutes before pouring the coal to them.

As you mentioned, you want the pistons, cylinder, and heads to warm up as uniformly as possible. Failure to do this, (especially in very cold conditions), can cause scuffed cylinder walls and pistons.
 
I'd rather idle for a minute or two to get oil to circulate under no engine load than under any load and no oil circulating.
And yes, I'd brush snow off and have rear window defrost on while idling, well it may take longer than 2 mins depending on how much snow and ice I need to clear.
 
Seen car dealers run NEW vehicles for 20 minutes or more with heat on HIGH with blower full steam to rid their stock of snow and ice . Also , know of others that let their car(s) idle over 30 minutes . I did same thing when younger and wised up a bit :rolleyes: . Remote start is the worse thing to happen with this . Doubt this could benefit vehicles with D.I.. 😨
 
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Seen car dealers run NEW vehicles for 20 minutes or more with heat on HIGH with blower full steam to rid their stock of snow and ice . Also , know of others that let their car(s) idle over 30 minutes . I did same thing when younger and wised up a bit :rolleyes: . Remote start is the worse thing to happen with this . Doubt this could benefit vehicles with D.I.. 😨
The remote start on my SRT and our RAM is limited to 15 minutes, after which point, it shuts off. This is generally long enough to get defrost working and the seats heated up.

Yes, I expect dilution with DI mills, which is already bad, would be even worse under these conditions. I'm not too worried about that with my engines, they are both port injected.
 
We don't have issues with starting in very cold weather here in the Bay Area. The lowest temp I've encountered that I can recall in the last five-six years has been 38-degrees. Most of my cold winter starts are, at worst, in the low 40s, although the majority of my winter starts are at higher temps.

That said, my routine is simple and consistent. Start the car, remove the sun shade, put on the seat belt, get comfy, and back out of my parking space. I'll idle or use a very light throttle to get to the gate to the street, the gate takes a few seconds to open, and I'm ready to drive away. The trip from my parking space to the gate is about 70 feet, so by the time the car is on the street oil and lube have circulated a bit, and the car's ready to drive. I take it easy for a while as I'm on city streets and near a school, and most of the time I'm driving on the streets at lower speeds anyway. If I'm going to hit the freeway, regardless of the direction, the car is nicely warmed and ready to go by the time I hit the freeway entrance.

Even if I'm in a hurry, I have to take it easy at least for a few minutes. If I had to deal with the very cold weather some folks here encounter, I'd probably do the same as I do now except use a 0W-30 oil instead of a 5W-30.

I should note that the Camry starts putting out heat pretty quickly. By the time I'm at the parking lot gate, the cabin's getting warm. This is a lot quicker than the Buick I had previously. I grew up with cold NYC winters, and am quite comfortable in a car without remote start, heated seats and steering wheel, etc.
 
Sorry, I'm not buying this damage from idling talk. I've idled my cars in cold weather for over 30 years, I've never had any increased wear or oil consumption and these engines range from 100-300K miles. Never a puff of blue smoke when first started.

I would like to see an engine teardown from one that idled continuously for 3 years. As well as one that has only been started in freezing temps then allowed to cool down, repeat for hundreds of cycles and never driven.

Imagine all the semi's that idle for hours that have a 1 million mile+ TBO.

I understand that the oil temp will rise more slowly and not burn off moisture as quickly, I see that as the only issue but IMHO, idling for 10 min over 2 min when cold should not be an issue. Honestly, I think it does a motor good allowing pistons to expand, fluids to warm for easier flow, etc.

When I see reports like this, I question their intent. It only takes one time like this to get something embedded into people's minds, and then they won't go back.

I'm also looking at this from a larger, more "upper management" view if you will with regards to global concerns and fuel usage.
 
As I grow older, I could care less. If I’m at work for 10 hours and it’s 5F out, I wanna get home and will gun it out of the parking lot 6K RPM if in the Audi, engine running for 30 seconds. Seems to hold up. I cared more when I was younger.
I have never had to rev a cold or even a hot engine to 6,000 RPM to get out of a parking lot. What's wrong with your parking lot?
 
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