I agree with the other posters that it is not necessary to allow the engine to warm up for more than a minute or two. You can hear when the oil gets to the top of the engine because the valves become quieter. I also agree that it should be driven gently until it gets nearly up to operating temperature.
"Starting it and running for just 30 seconds and shutting it off is hard on the engine"
Joe I don’t believe anyone suggested running it for 30 seconds and then shutting it down.
Isn’t 0 less than 32??
I understand about the moisture, but within 10 minutes of starting the car for 30 seconds and shutting it back off, my wife gets in and takes off, driving for about 30-40 minutes before she reaches her destination. Do you still feel that I am doing more harm than good by continuing my morning routine?
You would have to ask a mathematician.
I taught my parents this. Don’t get in the car, set the seatbelt, the mirrors, etc, then start it and drive. Start it, then put on your belt, check the mirrors, set the radio. By then, you’re good.
I, myself, just wait for the idle drop. It means the computer has caught up and all is well. In my new car that is about 10 seconds. In my 1995 Ranger that is about a full minute and a half. Then I drive easy until the temp at least registers on the gauge.