about 5 minutes…10 depending on ice/snow.
the amount of people in this thread that think idling a engine is bad blows my mind. YES there is sufficient coolant flow to not overheat you engine. YES there is oil pressure, not only do you have plenty of oil pressure but you have HIGH oil pressure because the oil is thick. The bad thing with cold oil is that it does not drain back as quickly as warm oil so if you start racing around you could suck the pan dry depending on your engine. idling your engine does not warm your transmission very quickly, and when you jump into your warm car you are likely to drive it more aggressively even though your transmission, CV’s, wheel bearing, and struts are all still far below the designed operating temp. Driving the car slowly for the first few min is the best thing for them because it bring all of the moving parts up to temp.
Higher than normal emissions are also a result of long periods of idling. Other than wasting gas there is no harm being done to your engine for idling it.
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