After starting, how long before driving?

[crazyoildude]

Warming up an engine before taking off makes sense! As for carbon buildup a minute or two won't accumulate that much if any carbon and besides what about cruising at a very low speed on my northstar at 40 mph the tach is just a hair above idle..
A properly warmed up engine wears less you can actually hear it..

 

[lui]

about 1-2min of idle time depending on how much of a hurry im in. i usually remote start the engine every morning just as im putting my shoes on to leave. so right when i get in the car its ready to go.

 

[addyguy]

On 'frosty' mornings, I start my car and let it run until the frost clears off.

In snowy weather, I start it, and let ir run while I brush all the snow off. In either case, car runs for up to 15-20 mins.

I don't believe in driving off until the glass is warm enough from the heater to keep ice from forming on it. I'm not going to drive down the road while my breath ices up the insied of the windows, or mositure uices up the outside of the windows....my safety is worth bit of gas that uses. I see it as a cost of living where I do. Kinda like having a pilot light burning all the time in the furnace or fireplace.

 

[KrisZ]

If you have to keep the car idling for 15-20 mins just to keep your breath from freezing on the windshield, then there is something wrong with your cooling system, most likley stuck open thermostat or clogged heater core. My car after just a minute will start blowing worm enough air to feel the difference between the ambient, and thus will prevent from fogging the inside of my car. For the outside we have scrapers to get rid of ice, snow and frost.

Sorry, I don't get your "safety" excuse, your idling is still wasteful and excessive, but like others said this issue will never go away because everybody has their own preferences.

 

[addyguy]

Oh, I don't need to run it that long - I usually go back into the house and do other things. I don't feel guilty about idling too much when I see police cars, busses, trucks, construction equipment idle for hours on end all over the city. My 2.2L does a heck of a lot less 'damage' than their V-8's and diesels!

 

[prax]

Originally Posted By: demarpaint
Not sure on the effect of an engine that was just started up and is idling at about 1700 rpms being tossed into reverse to back out of the driveway. I let mine idle down to just under 1000 rpms before I put it into any gear.


I'm sure the engineers thought of that. Something like that is hard to miss.

 

[Rand]

rather than idle my car for 15min at 0 degrees.. I just let it run for about 1min then drive gently. The load of driving makes it warm up within 2-3 mins of driving.

I cant imagine idling cold for 20min is better on an engine than that.

Unless you have a heat exchanger on the oil it wont warm up very fast either when its below 0.

I'm not saying start it and put it in reverse before the starter noise fades away but anything over 2-3min is unnecessary.

However, living in the free world has its advantages.. If someone wants to start their car up and let it idle for 3 hours.. they can who cares.

 

[hal]

Cold or warm ambient temp, I'll always let the idle speed settle to normal before going anywhere. This can take anywhere from 15 seconds to a minute or two depending on how cold it is. If it's below about 35-40F outside I'll let it idle for a minute extra, but not too long. I tend to agree that an engine heats up more the way it should when you drive it easy as opposed to letting it idle for a long time. Also, anyone who does let their car idle for longer periods should know that the transmission will never warm up until the car is driven.

 

[cjhepburn]

For AT, transmission cooling lines loop through the radiator. It warms as the car warms.
The lubricants have operating temperatures. I believe that the lubricants will not fully protect until they reach that operating temperature.

 

[HyperJinx]

I can hear a change in engine sound (quieter) after about 2min, thats when I take off.

 

[pavelow]

In the spring, summer and fall, we only let our vehicles idle for about a minute on the first start of the day. Every start after that, the vehicle is put into motion as soon as the dash idiot lights complete their self test...so like 10 seconds max. Now in the winter, for the first start of the day, we let them idle for the length of a song (2-3min) or until the snow is removed off the windows and it's safe to see out of them. Every start after that, the vehicle is put into motion as soon as the idiot lights have done their check.

 

[Martin1974]

Do not let it idle long at all. Just long enough to let the engine sort of idle down. Idling just wears the engine out without putting miles on the car so it doesn't make sense in that regard. It also seems to cause leaks plus it is a waste of gas. I am a mechanic in the Army and we have trouble sometimes with guys idling the trucks to stay warm or cool for long periods of time. You can tell because they seem to have more leaks. Bottomline, it just wears the engine out for no reason IMHO.

Just take it easy til the engine warms up.

 

[esco]

Your idle rpm range is higher during a cold start so that the engine doesn't sputter and die out(and probably for emissions), not necessarily because it's some kind of intentional warm-up timer or whatever other theory someone out there made up. Engine oil circulates through the engine far quicker than most would expect imo, if you drive the car then the faster the oil warms up and the faster warm oil is circulating through the engine vs idling where the engine is running on cold oil for a much longer amount of time in addition to the dirtiest most inefficient combustion cycles going on inside the cylinders.

To pull out of the driveway and floor it is one thing but to gently drive a car at low rpm's up to operating temp is perfectly fine and recommended by auto manufacturers. Usually by the time you start a car, put on your seatbelt on and fiddle with the stereo more than 30sec's has passed in my experience.

 

[Captain_Klink]

very simple, plug it in on a timer, so you can start and go. if no timer, and it is very cold, let it run for a minute, and then go, but drive very gently for the first mile or so. NEVER apply full power until engine is properly warmed up.

If you can do it, install BOTH an oil pan heater AND a block heater. That's what I do, and the engine loves it. Also, the cab gets hot right away too, so I also like it.

 

[HyperJinx]

1hr of idle is equal to 33 miles of driving.

 

[TiGeo]

I get in, start it, back out and drive. I never warm it up, I am of the opinion that it is a waste of gas.