What is the function of the engine tachometer?

1. Reflect the engine working status

The power of the vehicle comes from the engine. The engine crankshaft transmits the power through rotation. Whether its rotation state is normal can intuitively reflect the working state of the engine. Many faults are judged by the engine rpm. Therefore, when the engine is abnormal, the tachometer can also help maintenance personnel to judge the fault. For example, when the tachometer pointer swings up and down at idle speed, it means that the idle speed is unstable and the speed is fluctuating. For example, when the vehicle speed was originally 120, it only needed 2200 rpm, but now it needs 3000 rpm to reach 120, etc.

Without a tachometer, you cannot directly see if there is an abnormality in the vehicle. For example, you cannot tell the difference between 2200 rpm and 3000 rpm by feeling when driving at high speed. Only by looking at the tachometer can you know the abnormality in time and repair it in time to prevent small problems from turning into big faults and causing dangerous conditions.

2. Manual transmission vehicle shift signal

For manual transmission vehicles, drivers need to shift gears according to the engine speed. When driving a manual transmission vehicle, the timing of shifting gears is very important. If the gears are shifted too early, the engine power will be weak and the acceleration ability will be poor. If the gears are shifted too late, power and fuel will be wasted. There may also be a big setback, which will reduce the comfort of the vehicle and may also cause great wear on the clutch plate. Therefore, it is often necessary to combine the engine speed and vehicle speed to determine the timing of shifting gears. For example, when the engine reaches 2000 rpm, it is time to shift gears. At this time, both sufficient power and fuel economy can be guaranteed.

3. Protect the engine

The engine will have different working conditions at different speeds. By observing the tachometer, you can ensure that the engine is working within a safe and reasonable speed range. For example, you have engaged the wrong gear, or there is some fault in the gearbox, causing the engine to run at 5000 rpm to reach 120 horsepower. By looking at the tachometer, you can find problems in time and avoid damage to the engine caused by excessively high speeds for a long time. At the same time, it can also achieve the effect of energy conservation and emission reduction. When driving on a smooth road, the engine is always kept running in an economic speed range, so the fuel consumption will be relatively low. The engine burns more completely, there will be less carbon deposits, and it is more conducive to extending the life of the engine.