How long to wait after starting engine in cold weather?

[TeryT]

Ok...i am guilty...i GOOGLED:

Idling Myth No. 3: Shutting off and restarting your vehicle is hard on the engine and uses more fuel.

Frequent restarting has little impact on engine components such as the battery and starter motor. Component wear-and-tear caused by restarting the engine is estimated to add $10 per year to the cost of driving - money that will likely be recovered several times over in fuel savings from reduced idling.

As a rule of thumb, if you are going to be stopped for 10 seconds or more, except in traffic, turn your engine off. (Source: Natural Resources Canada.)"

This one I wonder about. I'm a fairly technical guy who has read technical preventative & predictive maintenance writings on this for almost 3 decades. One of the roughest things you can do to any device is to start it up. This pertains to both electrical & mechanical things.

In electrical things, when you turn them on, there is a sudden rush of current. This rush of current causes the component to go from one temperature to a higher one quite suddenly. This produces stress. Ever notice a light bulb blowing out when you first turn it on? It often makes an audible noise as its "life" is ended! (Some electrical motors can be designed to run tens of thousands of hours on continuous run. How? Because they don't have to start & stop.)

A mechanical device is overcoming dead stop inertia. There is, as a matter of physics, considerable stress put on the various components as they go from a dead stop to high RPM.

In an electric motor you have an electro-mechanical device. In this situation, both electrical & mechanical factors apply. In a gasoline engine, it is primarily the mechanical inertia to overcome from a dead stop (but the starter experiences both).

I can appreciate the studies done showing that idling causes other detrimental things to occur. I'm not arguing that. Certainly, at some point, long-term idling makes no sense. I'm just wanting to point out reasons why constantly starting an engine might not be prudent.

Now back to the original question. Modern engine oils are such superior lubricators that many of the practices of years gone by are negated. I'm not expert on lubrication, but I've read many times that the additives in modern oils do a much better job of keeping the cylinder walls lubricated, even while the engine is shut down. This is even more true with a true synthetic oil. Therefore it is not as critical to ensure oil has thoroughly lubricated the cylinder wall with fresh oil on start up.

Many think that our current gasser engines are built far superior to ones from years ago. While it certainly may be true that there have been good progress in this area, I've also read many times that engine longevity is due primarily to the advances in oil additive technology.

 

[atomic punk]

Time?
As long as it takes the 4R to reach 68 degrees in the cabin and the windshield is clear, summer or winter.

 

[BC4Runner]

At 10 degrees I'd have to let it warm up a long time.

 

[nyc4runnin]

i just let it warm up until the temp needle moves bout half an inch up

 

[atomic punk]

Two seperate concepts in the same thread: moderate climate or cold climate driving.

Idle less than 1 min in a cold winter morning before driving off???? You gotta be joking.

I might as well drive my jeep the 10 min to work every morning - with the top down and doors off to get the same effect. NO thanks. I plan on keeping the 4R for 7-8 years. Idling for 10 min every day won't have a negative impact on the function of the vehicle during the time I plan on owning it. If it does, then I bought the wrong vehicle for the Northeast.

 

[G-Spotter]

Since I live in sunny South Bay Southern Cali (south of LA)we dont have a problem of real cold weather here. 50 degrees farenheit is too cold for us here but you will still see people surfing at the beaches.
Forecast tomorrow they said will be highs at 84 deg here while u guys in the east coast and in the northern border will get about some 10" inches of snow and a lot of air flights will be cancelled again as in the past few days. Man, what a mess there with this El Nino stuff.
Anyway, I always wanna try to warm my engine after startup for about 5 minutes since I only drive 3 miles to work. But I always end up taking off few seconds after startup because Im gonna be late clocking in for work.
I read somewhere that the battery wont last long for short trips like that since the batt doesnt get recharge back long enough after giving up high current on startup. And I experienced that on my 92 yota Previa.

 

[VT 4-Runner]

The condensation thing doesn't matter with modern stainless steel exhausts.

It's not a matter of condensation in the exhaust, but in the crankcase. Short trips (under 10 miles) don't allow the engine to get warm enough to evaporate the condensation which winds up in the oil. In extreme repeated cases it can ad up to enough water to compromise the oil.

 

[twitchee2]

I usually let it sit for about 1-5 min depending on how long it takes my sister to get out here so we can go to school. I try to get warm air going before i go. Here is socal its cold at 55* . My parents just start and go for the entire life of the car so far. It still going strong.

 

[Koz]

It has been proven that the best way to heat modern engines is to give them a few seconds to get the oil circulating through the whole engine and then drive the vehicle at low RPM until reaching operating temp.

Koz

 

[rook]

I usually let it sit for about 1-5 min depending on how long it takes my sister to get out here so we can go to school. I try to get warm air going before i go. Here is socal its cold at 55* . My parents just start and go for the entire life of the car so far. It still going strong.

Rub it in, So Cal! We'll be 70deg colder than that this winter.

It has been proven that the best way to heat modern engines is to give them a few seconds to get the oil circulating through the whole engine and then drive the vehicle at low RPM until reaching operating temp.

Koz

I agree, and this is consistent with advice from owners manuals, mechanics advise and the two resident experts at Car Talk. I give the engine just enough time to stabilize and then drive conservatively until warmed up.

 

[ALt4r]

and the two resident experts at Car Talk.

That show gets worse every time i hear it!

 

[KellyJ]

I let my car warm up for a good 3 to 5 minutes in the cold weather and a little less when the weather is warm. On my 4Runner its impossible to run the engine to redline until the left temp gauge has reached its usual spot at halfway, even when you floor it. For some reason I never like driving my car until its relatively warmed up.

 

[4rnr4me]

My technique is to wait until the RPMs drop to normal, THEN I drive it real easy, no stepping on the gas or hard braking til the temp is about normal.

 

[cweta37]

I think it mostly depends on the vehicle itself. I had an 85 corolla, an 85 accord, a 03 civic and my runner... they all needed a lil waming in the cold mornings... but the older ones needed longer and all of them didn't need to warm up in the summer! the winter time it only gets to be in the high 30's.

 

[Methodical]

I wish i could define cold as in the 50's.

When thinking about cold weather, I think -40.

for that I warm the vehicle up for 10 minutes. I leave the cabin heater off while its warming up, or it won't warm up at all because the outside air will sap the engine of too much heat.

here in alaska we also plug our cars in. All cars here are equipped with separate heaters for oil pan, battery, transmission pan, and a block heater. Some don't have the tranny heaters.

its at -40 that you know synthetic oil is worth every penny

 

[Ruffian]

It's not a matter of condensation in the exhaust, but in the crankcase. Short trips (under 10 miles) don't allow the engine to get warm enough to evaporate the condensation which winds up in the oil. In extreme repeated cases it can ad up to enough water to compromise the oil.

I'm moving in a month, closer to work. It's less than 2 miles, and if I hit the ONE light wrong say less than 5 min. commute. So by reading this whole thread, I'm not sure which way I'll do more damage to my T4R. By letting it run too long in the morning, or by driving it cold right to work and then shutting it right off. Now I'm really confused.
I guess ride the bike. Which I will do as soon as it's not less than 40 deg. outside.

 

[MT4runner]

i usually wait like 10 minutes....its freaking cold here. i go and start it up before i head to school, its usually right around 0-5 at 6:30 in the morn. i wish i could call 55 cold....
today was actually decent, high of 15 degrees.

 

[KellyJ]

I feel you on that. Tomorrow's high here will be 13. THIRTEEN DEGREES. AS A HIGH FOR THE DAY. Why oh why did I ever decide to go to school here...

Should I prepare my car somehow? The coldest it's used to being exposed to is like the 30's. It's supposed to get into the negatives here soon

 

[4rnr4me]

yea it gets like in the 50's here BRRRRRRRR lol

 

[T?@\7]

if i feel like letting my truck warm up, i wait until i hear that sound, the 'system pressurized' sound. i dont know what it is, but have loved it since day one. maybe like 45 seconds after start