what does a tachometer do

• 2022-01-05

The tachometer is used to display the engine speed. You can visually see and know the engine speed, and remind the driver not to exceed the engine speed limit, so as to prevent the engine speed from damaging its internal parts and affecting driving safety! In particular, vehicles with t (turbocharging) judge when they start to work according to the engine speed. For example, vehicles with low-pressure turbocharging generally start to work at 1800-2500 speed, and vehicles with high-pressure turbocharging generally work at more than 6000 speed. The driver can control whether the turbocharger works according to the speed, Avoid the invalid working time of turbocharger, protect and prolong the working life of turbocharger.

Let's start with ignition. The speed of a four cylinder gasoline engine usually reaches 80 revolutions per minute to ensure successful ignition, but in order to ensure ignition quality, the actual speed will reach 120. For big guys like V6, the speed must reach more than 140. If there is no tachometer, I don't know what's wrong with the engine. Some cars are very quiet at idle speed. Some people with a big heart may forget that the car is still starting. In this case, you won't make mistakes by looking at the tachometer.

And the start. At the moment of engine starting, the speed often reaches 1200-1500 rpm, which is higher in cold weather. However, the speed should not be too high during cold start, because the lubricating oil does not reach the upper part of the engine at this time. In order to reduce wear, 2000 rpm is more appropriate. When the engine condition is stable, it will drop to 800 at idle speed. There is no tachometer, and there are problems in the initial stage, so we can't quickly judge and eliminate them. This is the use of the tachometer.

In addition, the tachometer can also prompt the shift timing of manual gear. Generally, the shift is the most smooth and fuel-efficient at about 2500 revolutions, and the power required is more than 3000 revolutions. We should also pay attention to the speed when driving. If the speed is too high (4000R / min), it will cost more. If we reach the red line, it will permanently damage the engine. Fortunately, most engines have speed limit function, which won't let you drive your family car as a racing car. In short, the tachometer is used to monitor the working state of the engine and let you know in real time. For senior drivers, listening to the voice and looking at the watch can judge where the car has failed.