Do you warm up your engine for more than a few minutes before driving? Well, the myth of having to idle their engines for warming up has been repeatedly busted. However, there are still drivers who believe that it is still best for the engine to be warmed enough before going for a drive. That could be because they used to drive older cars that use carburetors or are just advocates of the to-see-is-to-believe mantra.
In that case, a famous channel in YouTube – Engineering Explained – has created and posted an educational video in which he used a thermal camera to show how fast a cold engine (at zero degrees Celsius) of a 2016 Subaru Crosstrek could warm up to a temperature of 50 degrees Celsius. At this temperature, the engine speed (rpm) begins to drop since there is already enough heat. Engineering Explained started off by stating that the Crosstrek hasn’t been turned on in the past 24 hours, adding that the ambient temperature is negative 5.8 degrees Celsius.
As soon as the engine was turned on, its speed jumped to 1,800 rpm. However, it wasn’t around five minutes and 20 seconds later before the engine speed began to drop from 1,800 rpm. At this time, the engine temperature has already reached 50 degrees Celsius, which is enough heat for optimal operation.
Engineering Explained, however, pointed out that it is not necessary for the engine to be warmed up for a few minutes before driving. In his video, one of the reasons was because of the oil that keeps the engine lubricated. He pointed out that engine oils nowadays have been formulated to work even at very low temperatures below zero. Depending on the grade, engine oil could still pump even at an ambient temperature of as low as negative 40 degrees Celsius. This means that even at negative 5.8 degrees Celsius, engine oil (0W in particular) could still work and pump.
So, unless you are in a place where ambient temperature is lower than negative 40 degrees Celsius, there is no reason for the engine to be idled and warmed up. Likewise, it is the responsibility of owners to make sure that their vehicles have the proper viscosity oil for the season. But if you are not so sure about this, you still could immediately drive your vehicle, but at a gentle pace without flooring the accelerator pedal – this could help the fluids get to their operating temperature.
There are also more reasons why it isn’t necessary to idle and warm up the engine. In the past, cars employed carburetors, which job is to is mix the right amount of gasoline and air in the engine. But if not warmed enough, the right mixture could be compromised. However, carburetors have been replaced by electronic fuel injection, which employs sensors to get the right mixture. Electronic fuel injection systems typically adjust to the temperature conditions to mix the right amount of gasoline and air. Idling and warming up the engine for a few minutes only wastes fuel and energy.
However, there are some people who do idle and warm up their vehicle engines, but not for the sake of reaching the optimal engine temperature. There are drivers who idle and warm up their vehicles in order to defrost their rides and to get rid of the ice, thereby allowing them to drive safely. They also practice idling to make sure that the cabin is in the right temperature when they drive – for the sake of comfort. Surely, you wouldn’t want to drive at a chilling temperature.