letting the car idle to warm up on cold days

[*B2*]

Well, I may stand corrected. If idling longer with more viscous fluid(even if it is slight) causes more wear on the engine than increasing revs, there is no reason to allow warm-up. I would really like to take a look at a scientific study, but a quick google search didn't net anything.

[willwren]

Trans fluid is actually WARMED by the part of the line that goes through the radiator. But that's only PART of the fluid when you're not in gear. To properly warm a trans would take about 5 or 10 minutes while shifting into all gears to fully circulate.

In other words, don't bother.

[LeSabreUltra]

If it's really cold, I let my truck warm up for a few seconds before popping it into gear and pulling out of the driveway. My truck is perfectly happy with that.
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[enslow]

If you dont have a block heater here you dont go anywhere in the winter.
That simple.

Also i idle my car for at least 10 minutes every morning.
A) Fluid viscoscity
B) Creature comfort.

Normally after its been on the highway for 10-15 it will stay warm if im doing errands.
Working is a totally different story.
In the winter i get up 15 minutes early just so the car CAN idle and warm up.

You also go "thunk thunk thunk" until your tires warm up and round out. I suppose you may have to go farther north though to actually get "frozen" tires. I must say I've never experienced that living here, not that I care to experience that kind of cold anyway.

[enslow]

I just read the article, and part of it makes sense, but part of it seems bogus.

1) Driving warms the car faster then idling. I'd have to agree with this.

2) 10 seconds is all you need. I noticed that it can take about 5 seconds for the alternator to putting out decent voltage in cold weather. I will usually wait until the voltage comes up before I make any additional electrical load demands on the vehicle. That's the reason I'd wait 10 seconds.

3) Idling hurts the car. I don't think I agree with this one, at least not for his reasons. They are saying engines idle in rich mode, and that is bad for the engine. Well, until the car gets into closed loop, it will run rich anyway.

4), 5) True, true.

6) Block heaters beat remote starters. I'd say these technologies are for separate reasons. If I had a remote start, I'd have my defogger ready to go on startup. Although, I don't think that's possible with the electronic controls anyway. For now, the only reason I idle is to get the windshield defrosted while I'm scraping ice on the outside. A block heater won't help defrost my windows much faster, it will just give me warmer air faster.

7, 8) true, true. But, just how bad for your health, that could be debatable. There's a hill beside our house and people gunning it up that hill dumps ugly exhaust into our house. That is probably worse for our health than our neighbour idling for a few minutes.

[LeSabre in Buffalo]

I get operating voltage instantly in my car. As soon as the ScanGauge kicks on after 2-3 seconds, it's showing operating voltage.

Our cars will suck down a fuel at a rate of a gallon per hour for the first 5-10 minutes of pure idling when started below 32*F. This slowly drops to the warm rate of 0.45 gph. That's a fair bit of gas idling the car for any extended length of time after a cold start.

The block heater in the Buick is nice since it heat-soaks the engine for a few hours with 90-100*F coolant. The engine doesn't want to shed that head very readily, so it's quick for full warmup to happen. And, if you're running around shutting the car off like on a shopping trip, the engine keeps that heat since the whole shebang and not just the coolant is heated.

[enslow]

I get operating voltage instantly in my car. As soon as the ScanGauge kicks on after 2-3 seconds, it's showing operating voltage.

Our cars will suck down a fuel at a rate of a gallon per hour for the first 5-10 minutes of pure idling when started below 32*F. This slowly drops to the warm rate of 0.45 gph. That's a fair bit of gas idling the car for any extended length of time after a cold start.

The block heater in the Buick is nice since it heat-soaks the engine for a few hours with 90-100*F coolant. The engine doesn't want to shed that head very readily, so it's quick for full warmup to happen. And, if you're running around shutting the car off like on a shopping trip, the engine keeps that heat since the whole shebang and not just the coolant is heated.

I wouldn't jump to say you get operating voltage instantly because it's probably rising to the operating voltage in those 2-3 seconds. It is possible mine is taking too long to come up to voltage, and I will be looking at changing something soon.

When our cars use gasoline at that high rate during idling, does the rate actually decrease as soon as you put the car in drive and start moving? My reason for asking is that if the high rate continues for 5-minutes even when driving, that means that the rate is not caused by idling, you are just wasting gas, and lots of it. If the rate actually drops as soon as you put the car in gear, then it really makes sense to put it in drive, just to get the fuel rate down.

I'll have to ask for one of those ScanGuages for Chrstmas next years. Santa, are you reading this?

[LeSabre in Buffalo]

Nope, the rate stays the same when the car's in gear. When it's in gear and driving for those first few minutes, it's something like 4-5 GPH on moderate acceleration. Warm, it's 3-4 GPH on the same acceleration. The consumption is so high at cold idle because the PCM trying to get the engine to operating temperature as rapidly as it can for emissions reasons, and using that extra gas to warm up the catalytic converter.

Do remember, driving soon after a cold start is warming up the engine quite rapidly, and dropping the idle fuel consumption far faster than just idling. Plus you're using the gas to get somewhere. So it's still better for your fuel economy, despite the high rate of consumption. Sitting, the car is getting 0 MPG, or using infinite liters/100 km compared to moving.

Summarizing: Except for your comfort, there's no good reason to not drive the car very shortly after turning it on.

[enslow]

OK, everything is as I thought it was then. I was only disputing their point #3 that idling hurts the car. I don't believe it hurts the car, but it does hurt your economy.

The only reason I will idle the car is to get the windows defogged. That's mainly because I can't yet see to drive, so while the car is idling and clearing the windows, I'm scraping ice off the outside.

Personally I don't use the block heater, even if it is kind of nice to get heat almost right away. In our weather the outside temperature is quite mild compared to your region. Cold temperatures for use are usually -1 to -2 C (about 30F). I'm starting to get some heat after about 3-5 minutes of driving anyway. A block heater would use household electricity, so any fuel savings would be almost completely offset by the cost of electricity, in my case. In colder climates, it does make sense.

[LeSabre in Buffalo]

My electric bill went up about $3 using the block heater 5 days a week for a month. I'm sure it saved far more gas than $3 in electricity over a month. Plus having usable heat very quickly is nice.

We're getting back down to mid-20's during the day and 14-15*F at night. The Buick doesn't like starting cold at 14*F, as it takes forever to catch. With the heater it fires almost instantly.

[enslow]

My electric bill went up about $3 using the block heater 5 days a week for a month. I'm sure it saved far more gas than $3 in electricity over a month. Plus having usable heat very quickly is nice.

We're getting back down to mid-20's during the day and 14-15*F at night. The Buick doesn't like starting cold at 14*F, as it takes forever to catch. With the heater it fires almost instantly.

It would make a difference when it's 14-15F. That would be -10C for us, and we don't get that cold very often. Besides, my wife gets the garage, not me!

[repinS]

You also go "thunk thunk thunk" until your tires warm up and round out. I suppose you may have to go farther north though to actually get "frozen" tires. I must say I've never experienced that living here, not that I care to experience that kind of cold anyway.

A set of performance summer tires will feel this way as low as 10C. Takes a block or two before its gone.

[Sadden]

Pretty warm here right now. -15C
I notice a difference in warm vs cold tires purely in traction.

In the GP GXP i don't get decent grip till they are warm even with Blizzaks.
And the "thunk thunk thunk" isn't that pronounced but it is there. Even with a winter tire.

Honestly if you dont warm your car up your not going to go very far here.
Warm moist breath plus cold windshield = Fogging up.

And here if you dont have a block heater your car wont start.
Period.
Coldest i have ever seen is -65C (-85F)
Im actually getting a heater that circulates the coolant and warms it.. Dial down the idle time.

Sometimes you will think your cars warm enough..
And then you hit the highways at 60 mph your windshield fogs up from being cooled by the wind.

Warm up time is very important here.

[redmetrix]

First of all I agree that engines in modern vehicles are designed to just start and go with no idle time to warm up. With that said I still let the Trans Sport idle to warm up a little when it is very cold out; it does sit outside.

If you go an YouTube, a number of people show the "piston slap" sound with their GM 60 degree V6 engines like the 3100/3400. In some cases the noise is pretty bad. This one gentleman explained how this problem is a result of not warming up the engine on very cold days. He said that GM designed these engines in a way where the components of the bottom end of the motor fit more loosly when the motor is cold (causing the slight knock noise) when the the engine gets up to temp, the metals have expanded and fit together for maximum efficiency. Driving with the engine in the cold state will cause excessive wear.

That explaination caught my attention and it does make sense to me. If it is, for example, 9 degrees F ouside, I let that 3400 idle for a few minutes. It has over 220,000 miles on it now and runs and shifts like new so a little idling is not a bad thing. Although if the temp is above freezing outside, then its just start ur up and go.

I do think it is totally unnecessary for people to let a vehicle idle while going in the post office ect.

[willwren]

Our engines are the farthest departure from a crappy 3400, arguably the worst engine GM ever built.

[Bonneville92V688]

the 3100/3400 series of the 60* V6 is terrible... I've seen them inside and out and they are horrible...collapsed lifters, poor intake gasket design, piston slap, broken camshafts, head gaskets, leaky plastic valve covers, etc. My 94 Century with 77k had terrible piston slap and lifter noise... plus the way I drove it didn't make it any better (It was my first car). Now the Iron head 2.8/3.1/3.4 and the early 2.8/3.1 MPFI? Totally different... I'd trust one of those like a 3800. I've seen both of those variants well maintained go well over 200k.

Either way... I strongly believe in at least 10 seconds idle time after starting.... like I said just to get the fluids moving. Carb'ed cars are different of course... I remember my Dad's '78 Cordoba had to sit at least a few minutes at high idle before it would even go... the Carter 4bbl on it sucked.

[sm in Georgia]

Sadden=

-85 F - wow. I have known it on rare occasions get down to 0 F but wow!!

block heater- only used on Diesels down here, I have never seen them on other cars

We had a 1985 Ford XLT Lariat (250) that was a diesel (International) and it was brand new - 1st tank of diesel I think! Froze up on the way home. Didnt have it plugged in because we were out and about. We were told to put a little kerosene in the tank during the winter.

This week my husband has been plugging his block heater in - but I do not remember him doing it before and it is a 2006 Diesel (Cummins)

I just cant get over the temps up there, My dad grew up in Kitchener Ontario and went to military school in Bismarck ND. He does not remember it being cold, but does remember playing in the snow. I am thinking his brain must have been numbed by the cold!!! But then I guess kids dont feel the cold like grown ups!!

[enslow]

Sadden=

-85 F - wow. I have known it on rare occasions get down to 0 F but wow!!
...
I just cant get over the temps up there, My dad grew up in Kitchener Ontario and went to military school in Bismarck ND. He does not remember it being cold, but does remember playing in the snow. I am thinking his brain must have been numbed by the cold!!! But then I guess kids dont feel the cold like grown ups!!

Temperatures and climate vary greatly in Canada. Parts of Michigan are actually farther north than Kitchener Ontario. Sadden must live in the northern reaches of Alberta. You're not going to see those temperatures in the US unless you're atop Mt Baker, and even then I'm not so sure. Some of you guys in the US get much more snow then we get here in Vancouver.

[Sadden]

Im the second most northern member according to our Phoogle map.

[LeSabreUltra]

Honestly I could see letting it idle for a minute or two where you live, at those temps.

I used to let my car idle for a minute or two back when I had my first car, but it was very dramatic about cold starts. Not that it had trouble or anything, it just put on a big show to let you know "hey I started in the cold, yay me!". It was a Honda curiously.

My truck (or my late Buick) puts on no such show. It just goes. Only difference I notice is that it seems especially torquey when the motor is cold, my guess is because of the extra fuel being dumped in.
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