To idle or not to idle? Warming an engine.

[Tommy McIntosh]

This is a topic that I've come across many times and I've heard multiple theories and dos and don'ts about it so I'm gonna ask you guys.
When it's freezing outside and the vehicle has sat overnight with no start ups, is it best to let it idle for about 10 or 15 minutes or just start up and drive?
Here's my thing, I let it idle, and theres a few reasons why.
First I don't like driving it right after starting it when it's that cold, I feel like it's hard on the engine and trans.
Second it doesn't hit overdrive when it's cold, and this isn't the only vehicle that does this so it's gotta be hard on the tranny.
Third my windshield is usually real foggy and the defrosters don't usually clear it until it's starts getting warm.
And last the power steering isn't that great either when it's cold so probably extra strain on it alao.
So what do you guys think? To idle or not to idle?

 

[Bobbylew]

This is a topic that I've come across many times and I've heard multiple theories and dos and don'ts about it so I'm gonna ask you guys.
When it's freezing outside and the vehicle has sat overnight with no start ups, is it best to let it idle for about 10 or 15 minutes or just start up and drive?
Here's my thing, I let it idle, and theres a few reasons why.
First I don't like driving it right after starting it when it's that cold, I feel like it's hard on the engine and trans.
Second it doesn't hit overdrive when it's cold, and this isn't the only vehicle that does this so it's gotta be hard on the tranny.
Third my windshield is usually real foggy and the defrosters don't usually clear it until it's starts getting warm.
And last the power steering isn't that great either when it's cold so probably extra strain on it alao.
So what do you guys think? To idle or not to idle?

The last thing I read and heard was that 30 seconds to a minute or two is sufficient for a warm up. When it's 30 Below, I would let it idle for a longer time, though. It's difficult to concentrate on driving when you're shivering! Short warm ups seem to make sense in warmer than Zero weather, given the electronic engine controls. On carbureted engines, a longer warm up was considered necessary, but today's engines are (supposed to be) running at optimum, shortly after startup. I don't hot rod it right off the git, however.

That's my story and I'm stickin' to it. LOL

 

[Number4]

During the warmer months, I let it idle till the RPMs drop below 1k.

Colder months, I wait until the coolant reaches at least 60°, but I have no real reason for it.

 

[boominXplorer]

When it's cold <30* I almost always let my vehicles run for at least 5 minutes. Mainly to clear the windows but my diesel needs to warm up just to get out of its own way. It takes my diesel about 30 minutes to get up to temp when it's cold outside.

Newer gasoline engine's are designed to be driven as soon as fired up. At the same time you need your windows to be clear to drive and heat isn't instant.

 

[Tech By Trade]

-12c here today, I will probably let it run for 5 min before I leave the office. Just to let the oil thin out a bit before I go.

 

[lincolnshibuya]

depends on what kind of oil and it doesn't really matter, the moment you start up your car at that cold temperature you already strained the engine. The rest is more of a preference since it will take a while to get warm air from the vent and clear up the window. A 0w20 or 0w30 grade oil helps.

as a bmw owner where it takes 0w40 (twice as viscous on our explorer) I have to let it pass the blue line in the temp gauge before I could rev it past 2.5k or 3k (as what the owner's manual recommended) That means I have to idle it for a couple minutes and drive slow until it warms up.

 

[MrPulldown]

New cars you do not need to idle much before you start driving. I usually give it no more than 30 seconds. There is discussion that says you should limit your idle time and try to bring the car up to speed as fast as possible, ie by driving it. The cold start enrichment mix is no good for the engine.

We generally park in a heated (not directly heated but attached to the house [1st floor] )garage, and often backed in. If I fill the garage with exhaust, it will eventually make its way into the house. SO I pull out almost immediately after starting.