CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Cold weather

My friend and I are having a minor argument about using the car in cold weather. Recently it was -10F outside. I commented that I was leaving the car parked and staying home. She said she had started her car to “warm it up” because it was bad for it to sit outside in the cold. I told her that it was bad to DRIVE the car cold but that otherwise there was no need to “warm it up.” Please note that this is only for one day and that we both have functional batteries. So tell me…Is it really better for a cold car to be started and driven than it is for a cold car to sit and do nothing on a cold day? Does it matter?

If the choice is between starting the car and not starting it, then clearly not starting it causes less wear. It doesn’t hurt the car to sit outside in the cold.

If the car does need to be started, then it shouldn’t be warmed up by idling. At -10, it would be best to sit for maybe 10 to 15 seconds and then drive gently until everything (not only the engine but also the transmission) is fully warmed up.

If you regularly see temperatures in this range, I’d start thinking about an engine block heater if you’re able to plug one in. That will reduce the wear of cold starts.

To what lion9car stated, I will add that, if your area typically has temperatures that are below 20 degrees in the winter, you should really be using synthetic oil in the engine.

In my area, winter temps normally do not go below ~30 degrees, and in the usual 35-45 degree winter temps, I only idle the engine for a few seconds before driving off. However, when the temp is in the -10 range, I do think that perhaps a minute of idling is a good idea before beginning to drive.

In any event, the car should be driven very conservatively until the temp gauge indicates normal operating temperature, as both the engine and the transmission are subjected to a lot more wear until normal operating temp is reached. Since the first road outside of my development tends to require pretty fast acceleration in order to merge safely into traffic, when it is really cold I will drive around the block slowly a couple of times before trying to accelerate into the 45 mph traffic flow on the county highway.

As others have already said…the best way to warm up a car? Drive it! (gently at first)

Agree with the previous posters. It’s -20 outside right now and dropping further to -25. Both our cars have block heaters which we plug in when we have to park outside. It’s a great investment. Agree that 0W30 synthetic is the best winter oil. It flows at -50 and will quickly lubricate the valve gear and bearings. At -30, a 10W30 standard mineral oil will take a full minute to properly circulate, causing a lot of wear.

At those temperatures, with such an oil, a cold start is about equal to 500 miles of driving in terms of engine wear.

I concur in full with all the previous posts. I’ll add that her car probably sat a lot longer that that at the dealership before she happened by to purchase it.

I also support Doc’s suggestion to have an engine heater installed. Block heaters are the most common, but I had a lower radiator hose heater (in North Dakota) and that worked great too. Either will keep the engine a bit above ambient over night, making it easier to start and quicker to warm up.

Can I also ask in regards to this please. I have heard on CarTalk where they have said with newer cars you don’t really need to let the car warm up when its cold outside unless it is really really cold (which to me at least less than zero). But that if you are jumping onto something like the highway and going highway speeds with a cold engine when your car isn’t warmed up thoroughly that is very damaging to your engine. So I am conflicted.

I live in a big apartment complex in Montana. My apartment is far away from where I park my car. I don’t want to go out and start up my car before I have to leave. However, when I do go out to leave I always seem to be cutting my time close and needing to leave right away plus they said you don’t need to wait to warm up the cars these days. I thought they said because they are not combustion engines anymore. Did I get that right or did I hear or remember that wrong? Anyways, I just leave after a couple seconds. I only live maybe a mile and a half from the highway, two tops, and my total commute is less than four miles. I am concerned that I could be damaging my car with it not warming up and then getting on a highway so soon and travelling such a short distance. Should I be concerned? It is a 2003 Toyota Camry. Should I change to a synthetic oil in the winter if I don’t use it any other time of the year?

There are a number of reasons you don’t need to let your car warm up anymore, One being the fact that motor oil has gotten so much better over the years, but cars still have internal combustion engines in them. You must have heard that wrong. I would let the car warm up until the fast idle has kicked off, then drive it gently to the freeway. Accelerate gently up to highway speeds and you should be okay by then.

Also be sure to take your car for long drives at least once a week or so and get it heated up to normal temp. for a time. Those short hops can be hard on a vehicle. I would also change oil at least every 3k miles in it especially in the winter!

It really doesn’t make any difference but if you are going to start it, then take it on a long enough drive to warm everything up. In college in Sioux Falls, I had a 59 Pontiac and one of my room mates had a 55 Pontiac. The first thing I would have to do in the morning is get my car started no matter what. My room mate didn’t really care. One -10 morning his didn’t start and he said he was just going to leave it until a warmer day. It drove me nuts but sure enough a few days later it started right up. I think its just a matter of personal choice. I can’t let a car sit outside without getting it going, but others have no such compulsion.

Thanks for the feedback, I appreciate it. This has been bothering me for months. I wish I had thought to post here sooner. Definitely glad to know cars still have internal combustion engines and that I didn’t say that infront of a crowd of people, especially given that I am blonde. Never would have heard the end of that misunderstanding.

My lawnmowers sit in an unheated storage shed all winter. I don’t have an overwhelming compulsion to go outdoors when the temperature is -10 degrees F and start the engines. In fact, I don’t feel an urge to start the engines when it is 75 degrees and the lawn needs mowing. I feel the same way about my automobiles.

MT254 wrote:
I am concerned that I could be damaging my car with it not warming up and then getting on a highway so soon and travelling such a short distance.

Cruising at highway speed isn’t a problem. Accelerating hard to get onto the highway is what you want to avoid if possible.

+1

Cruising at highway speeds probably means that your engine is turning over at somewhere between 1,600-2,000 RPMs. By contrast, accelerating onto the highway might result in your engine turning over at…4,000-5,000 RPMs, depending on how hard you are accelerating, and those high RPMs are damaging when the engine and its oil are cold.

My advice to MT254 is as follows:

Get up about 10 minutes earlier, and watch the clock carefully so that you aren’t always running late.

Consider getting a remote starter installed, so that you can start your engine from the comfort of your apartment. Be sure to get a remote starter with sufficient distance capability for your apartment complex.

If you don’t get a remote starter, get into the habit in very low temperature conditions of allowing the engine to warm up for at least a minute or two, and then drive very conservatively until the temperature gauge is in the normal range. If you drive about 2 miles to the expressway, the engine should be warmed up sufficiently after a minute or two of idling and a few minutes of conservative driving.

Consider switching to synthetic oil for at least the winter months. The engine will actually start more readily, because there will be less “drag” on the engine with synthetic oil. If you want to switch back to conventional oil for the summer, that is not a problem. If somebody tells you that this is not adviseable, you can tell him that his theory was debunked at least 10 years ago.

On weekends, get into the habit of taking the car out for a highway drive of at least 40 minutes, in order to “burn off” all of the water vapor that has built-up in the motor oil during the week. This will also help to dry out your muffler and extend the life of the muffler and tail pipe.

“they said you don’t need to wait to warm up the cars these days. I thought they said because they are not combustion engines anymore.”

I see too many people warming up thier trucks when it is 65 degrees out (wasting fuel), but this comment makes me wonder how many Nissan Leaf owners “warm up” their car before driving.

The Nissan Leaf is all electric; no gas motor. If you own one there is no need to warm up, but you should not drive off at top speed immediately. The bearings are very cold and they need gentle driving for a mile or so to avoid rapid waer.

Today’s cars have fuel injection and get the right amount of gas immediately. The reason for running the engine for 20 seconds or so is to let the oil in the engine circulate to the valve gear and the bearings. Think of it as humans needing some warm up atslow speed before they start running.

You can heat/cool down up the leaf via your phone. Its actually a smart thing to do because then you aren’t drawing from the battery for the initial heating/cooling; it’s coming from the house power. Of course it does get the power train warm, but at least you stay warm.

“Of course it does get the power train warm, but at least you stay warm.”

I believe that you meant to tell us that “it does NOT get the power train warm”.
Yes?

Yeah, does NOT get the power train warm.

I usually let my car run for a minute or two when I get up in the morning to take my son to the bus stop…The only time I let it sit and idle is when there’s ice on the windshield and I want to melt it a little with the defroster before taking the Ice Scraper to it.