“People who take care of their cars are more worried” Is it necessary to warm up the car? I asked an active mechanic | MOBY [モビー]

What is warm-up operation?


Warming up is the process of raising mechanical parts such as the engine to an appropriate operating temperature by idling or low-load operation. Generally speaking, the stable operating temperature of an engine varies depending on the vehicle type, but the water temperature is around 70 to 90°C, and the oil temperature is around +10°C, and it is said that the temperature range in which the engine can operate most efficiently. .

Also, in order for the transmission and suspension to operate stably, a certain amount of heat must enter. If we were to use a human analogy, warm-up would be a warm-up before exercise.

requirement? No need?Opinions are divided on warm-up

© Stefan Redel / stock.adobe.com

Opinions tend to be divided as to whether warm-up is necessary or not. In addition, opinions are divided on whether to warm up while idling or warm up while driving.

Cars in the days when carburetors were used for fuel supply required warm-up with an eye ring. When the engine is cold, even highly volatile gasoline does not evaporate sufficiently, making it difficult to run without warming up the engine.

In addition, since hardened oil was used, it was not possible to circulate the oil sufficiently when the oil was cold, and the clearance of each part of the engine was wide, so it was difficult to generate power when it was cold. I couldn’t start running unless I warmed up until the engine had a certain amount of heat.

At present, warm-up operation is becoming unnecessary.

Electronically controlled fuel injection devices have come to be used for fuel supply, and today’s cars can control each temperature zone to provide stable fuel supply even when it is cold. In addition, the machining accuracy of the parts has been improved, and the thermal expansion change inside the engine has been minimized. Due to the advancement of these engines, it is now said that a long warm-up time at idling is unnecessary.

Furthermore, in recent years, “idling prohibition ordinances” have been enacted in some regions, and unnecessary idling is prohibited. In addition, the idling warm-up is moving toward elimination in order to reduce fuel consumption during idling and promote a rapid temperature rise in the engine and catalyst.

As the instruction manual for the car states, “It is not necessary to stop and warm up” and “Start driving immediately unless the car has been used for a long time or when the temperature is extremely low.” became.

After all, you don’t need warm-up, do you?

However, just because you don’t need to warm up doesn’t mean that you can go full throttle on the highway or circuit immediately after starting the engine cold. As long as the engine has an appropriate temperature, some form of warm-up is necessary. Ultimately, what is the best way to do this? I asked this question to an auto mechanic.

Leave a Reply