Originally Posted by mmarshall

Don't just start a cold engine and let it idle without moving until it is at normal temperature. Let it idle until the oil pressure comes up.....that will take from about 10 to 30 seconds depending on outside temperature, engine condition, oil viscosity, and oil type...synthetic or petroleum. In really cold weather, without a block heater, you may want to let it idle for about two minutes or so to make sure the oil is warm enough to be flowing freely.

Then take off and drive GENTLY (below about 3000 RPM or so) until the coolant temperature is about 140 degrees or so...roughly the lower mark in the normal zone on the temp gauge. An engine is considered warmed up at 140 degrees, and can then be driven harder, though the thermostat usually doesn't open till about 195-200, and the cooling fan clicks on a little higher than that.


You guys are also forgetting about the transmission and differential fluids. THEY have to warm up, too. Letting an engine sit still while it warms up does NOTHING for those fluids to help THEM warm up. The best thing is to just drive slowly and gently for the first couple of minutes, warm ALL the drivetrain fluids up at once, and then drive normally.

Most engines, by actual testing, warm up more quickly and efficiently under a light driving load than when sitting still....and, of course the transmission and differentials heat up as well.


This, of course, refers only to normal, traditional gas and diesel engines. With Gas/Electric Hybrids, of course, the computers determine when the gas and electric motors cut on and off......which, of course, is determined by a number of factors relating to temperature, engine load, and state of battery charge.

Originally Posted by geko29

Idling is bad for the engine, ESPECIALLY when the oil is cold.

Originally Posted by toy4two

lots of auto cars, my Lexus included, will keep your car in 2nd gear to speed up warm up, including warming up the catalytic convertor for peak efficiancy. Others with turbos will run conservative boost until the engine is fully warmed up.

Originally Posted by mmarshall

Yes, some vehicles do have a transmission lock-out for the upper gears at cold temperatures (fortunately my Outback doesn't).........I find that feature annoying. It does speed up engine and transmission warm-up a little, but also tends to jack the engine RPM up unnecessarily as well, so you have to be doubly careful and drive even slower to stay below 3000.......while impaitient jerks behind you fly by and show you their middle finger.