I exactly do that too but when I park the car at night, I leave the front windshield defroster on cuz it suck in our car. When I start the car in the morning the defrost will start too and I will drive slowly until the engine warm up. I was told that you need to drive the car so the engine can warm up faster.

 

I agree and have dealt with that too. I immediately throw on the front and rear defroster then just scrape. De-icer fluid is also nice and helpful.

 

Problem with the front defrost when it's cold out is that it takes almost 10 minutes before it even puts out enough warmth to clear the fog on the inside of the windshield. Doesn't matter if the outside is scraped.

 

With regard to the engine, warming it up fully while idling is a waste of both time and money. The initial 30 seconds period is required for the oil pump to push the oil in all of the engine's oiling circuits.

From the Owner's Manual for my G37S M6:

"Allow the engine to idle for at least 30 seconds after starting. Do not race the engine while warming it up. Drive at moderate speed for a short distance first, especially in cold weather. In cold weather, keep the engine running for a minimum of 2 - 3 minutes before shutting it off. Starting and stopping the engine over a short period of time may make the vehicle more difficult to start."

 

"Starting and stoppin the engine over a short period of time may make the vehicle more difficult to start"

I believe this is in reference to using conventional oil, which is what the car calls for, but for those that use fully synthetic oil, it can handle the short trips in cold whether because the oil is finer and gets to temp almost immediately. Conventional oil takes time to thin out and can create sludge build up with those short start/stops making the possibility of harder starts.

 

That may be related to a "marketing" strategy. No one would buy the car, if the manual said "warm the car for 7 minutes before you take off". Engineering and marketing do not go hand in hand most of the time.

 

Oil viscosity should be the reason why you let the car warm up for 60 seconds which most of those old internet articles don't really get into. They all associate it with carb's. I'm a aircraft mechanic, i can't stress enough bringing oil up to operating temperature is important for the longevity of a combustion engine.
That sluggish feel is not only the oil still congealed lets say on cold days, but so isn't the tranny fluid. That high idle noise, that dissipates after warming up is the engine taking in account the oil temp. It all has to warm up to operating temperature.
How much money could possibly be "wasted" for an additional 30 seconds of idle lol. 60 seconds should be enough, but all will vary on each car. Listen, the engine noise tells all.

 

All the more reason to use full synthetic, especially in cold weather. It stays thinner at cold temps.

 

Well, it's not thinner, a viscosity rating is a viscosity rating. It's the additives in synthetic that makes it less likely to firm up/congeal in colder weather. Hard to go wrong with synthetic for sure.